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Small Wonders The World of Nanoscience
Dr Horst Strmer Lecture
Czech Technical University
10/19/2006
Horst Strmer:
Good morning everybody, its a great pleasure to be here at the Czech
Technical University. Actually, its also a great pleasure to be in a country
where they know what an umlaut is and you have all these little hyphens and
bars on top of your letters and you know that theGermans have too. And
when I was born and I had two dots in my name and it disappeared in the
United States because Americans do not know how to handle umlauts. So, a
colleague of mine told me, Just drop them, they do not know how to do it.So, for twenty three years of my life that I lived in the United States, I didnt
have an umlaut and then we won the Nobel Prize and the Germans came
back and said, You do not have an umlaut? and I had to admit that I had
an umlaut so, ever since, I have had three times, once without an umlaut,
once with an oe and once with an umlaut which cut my publication record
by a factor of three! So its good to be in a country where you understand all
of these things that are on the top or the bottom of letters. Im really very
pleased to be here.
In fact, I was thinking about this as a technical University and thats
particularly why I appreciated it because, although all of my education and
training is in the sciences, I think deep down Im really an engineer. In fact,
Id probably be a much better engineer than a physicist! So, Im looking so
much forward to the things that were going to see tomorrow. I think,
maybe, already Sunday afternoon and Im sure that Im going to enjoy it
very much.
I said Im pleased to be here and Im pleased to be here in spite of the
schedule whichmeans that I have to give four hours of lectures. Ive donethis only once before in my life and, in fact, to disastrous results but, at the
end of the day, over dinner, I couldnt remember any more at what
University I was. Im sure this will not happen here because this is, of
course, going to be a very solid eventand I will have all of these impressions
that will not let me forget this University Im sure.
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What I would like to talk to you about, Im giving two lectures and I said
already Ill give you four hours of lectures and I hope, at the end of the day,
you will not be tired of me so this is a public lecture and, in the afternoon,
therell be a second lecture which will be a little bit more specialized but
dont be concerned about it. It still is a colloquial so I invite you all to join.
Its a bit more technical and much more to what I mostly actually do in
terms of research.
This public lecture is very much along the line of what Im doing with many
colleagues at Columbia and I want to give you a sort of broad overview of
what nanoscience is and I think where its going and why its so interesting.
In fact, at Columbia, we have a Nanoscience Centre which is funded by the
National Science Foundation. Its one of the first six that was funded. We
are about sixty people: about twenty faculty; about twenty students; about
twenty post grads. We particularly focus on the electronic properties on thenanoscale so the talk that I am giving you today is a public lecture. Its
meant for a very broad audience and it tries to point out where I think,
presently, the interesting aspects of nanoscience are and, more so, where
things are going in the long run.
So youve probably all heard about nano. Certainly around the university
its not a word that hasnt been heard before but nano really came on the
stage, I would say, just about ten years ago as something that was recognized
by a broader, I should say, the broader public to a degree which we all know
nowadays, well I suppose most students know what nano is ever since this
little gadget came on the market which is the IPOD Nano and, although this
is not really on the nano scale, it certainly is along the line of what nano
means in the meaning of the word its the new word for dwarf, its
something small. Not everything that is nano is really on the nano scale
because, of course, inside there are things that are not nano. Some of the
things that you see in a nano are not that serious. Here is something called a
Nano reef which is really just a very small aquarium with very small fish
in it. So the word nano is being used in many senses and not always along
the line of what nano actually means. And, as we all know, nano reallymeans just one billionth so, one nanosecond is one billionth of a second, a
nanogram one billionth of a gram and a nanobrain would be a very big
insult!
So, nano really means just one billionth and one billionth in the sense of a
meter and, although, as this audience is well aware what a nanometer is, I
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mean we should still put it on a scale. If you have one billionth of a meter, it
also means one millionth of a millimeter and one thousandth of a
micrometer. So, one nano is really just about what you can see on a
microscope because what you can see on a microscope is roughly, sort of a
micron. All the way down to the atomic scale but not quite to the atomic
scale. Its really above the atomic scale. A nanometer is about five to ten
atoms in a row and its actually a very important aspect. The nano scale and
the atomic scale is not the same scale. The nano scale is above the atomic
scale because it doesnt deal with individual atoms but it deals with an
assembly of atoms and that is what is the important aspect of it. When you
take an iron atom while it is in steel or you take an iron atom which is the
same iron atom and you look at it while its in hemoglobin, it is very very
different. It has a very different function in hemoglobin than it does in steel
and what makes the difference is, its not the atomic scale but slightly above
the atomic scale and the environment matters.
Its the first time that things can be put together and make something of
interest to us, so let me bring to you a movie that you have seen before and I
want to put this into a little bit of context of the length scales that were
familiar with. Ive shown you a movie. This is a movie pack of ten so every
slide shows you another pack of ten starting approximately at the scale of the
universe we are working one thousand times smaller than the scale of the
universe. I just want to put the nanoscale in perspective of all of these
length scales that we are dealing with.
So as were going down orders and orders of magnitude, the whole thing
always looks the same, just on different scales, and eventually at about ten to
the nine meters, we come up with something that were familiar with, the
Earth. And thats on the scale of about a hundred thousand kilometers and
as we go further down, were diving actually into Florida. This is a magnet
lab into Florida where were working quite often, a leaf and down into
beginning at a micrometer, one micrometer. So, this is the nanoscale: a
hundred nanometers, ten nanometers, one nanometer, and were diving into
an atom, into the nucleus and into the core and then we get into the nth scalebut we really dont know whats going on once we get to the nth scale. So,
on this length scale, from the size of the universe all the way down to the
sub-atomic scale, typically as a physicist, all of these length scales have their
particular attractions. And here we try and understand how the universe
came about, what dark matter is, what dark energy is nowadays. Down at
the other end of the length scale we find understand what mass is, how mass
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comes about how elementary particles come about and even much further
down, almost mathematics on somewhere string theory. Again, trying to
understand what happens on this length scale and the nanoscale sits
somewhere right smack in the middle.
So, what is so interesting about the nanoscale? To put it in one word, its
complexity. Its for the first time where you can put atoms together to
make some things which are called interesting, call it complex and we will
come back to this, but before doing this, let me actually agree the nanoscale
with this audience here or to this lecture hall.
So, let me just get a feel for how small the nanoscale is. So, let me do
something that I should do less and less often at my age and my hair color
which is pull out a hair. Ive found one! And we look at this hair which, at
least at my age, is about the smallest thing that you can see! I got two. Ishouldnt do this! This bodes poorly for my future. So, you pull out a hair.
This is about the smallest thing that you can see. Now imagine that we blow
up this hair to the size that you can touch the atoms which would make the
atoms as big as, well usually I would make the atoms as big as basketballs,
but, because were in Europe, well make them as big as soccer balls which
here is called football Im sure. Thats at least the way we call it in
Germany too. Football. So, we make it as big as a football.
So, this hair we now place on top of a CPU, just lying on top of CPU. Now
guess how big this hair is. Now guess how big this hair is. Now, sure, you
can all calculate it I know but just have a quick guess. How big is the hair?
This hair is now lying on us. Im standing under here. The hair is lying on
the University and covering Prague. How big is the hair if the atoms are as
big as soccer balls? Well, heres a map of Prague and this is how big a hair
would be if we blew up all the atoms to the size of soccer balls. No sun
from Vichy to Melnik No sun over Prague and thats only in this direction.
And thats all soccer balls and everything blocked out. So, this is as big as
just one hair would be if you had the atoms as big as soccer balls. Now, on
that scale, if the atoms are as big as soccer balls, the nanoscale is about thesize of this auditorium or about the size of this stage. So, this is the scale on
which one is operating when one is dealing with the nanoscale. And were
very comfortably operating nowadays on the nanoscale already.
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So, let me point out to you a little bit the challenges but also the
opportunities that exist on the nanoscale. So lets start out with an atom and,
of course, this is a very poor rendering of an atom
Heres an atom and I recall very distinctively in the early eighties having
been on a committee with Physics Today which is a publication of the
American Institute of Physics and having across from me sitting John
Hopdales who is a physicist but then also a biologist but he said at some
point, But atoms, atoms are boring! and I was shocked because, as a
physicist, I mean the atom is the demonstration of quantum mechanics. We
can measure everything, we can nowadays calculate most of the things. But
he said, But atoms are boring and, in a certain sense, hes right because an
atom is basically like a Lego block and, just like an individual Lego block, it
is not that interesting. This is actually the son of a colleague Colin Marples
whos a chemist demonstrating to you how interesting a single Lego blockis. Lego blocks by themselves are not interesting.
Whats interesting is what can be made out of them and I do not want to say
that atoms are boring but certainly what comes to be interesting is what you
can make of them and that doesnt happen on the scale of the individual
atom but it happens at a bigger scale so if the individual atom is boring or
not that interesting then let me show you something thats interesting. This
is only atoms and yet something comes out of it that you somehow wouldnt
be able to see in the atom. You can calculate the atom until the cows come
home but we would not imply the existence of something like that.
Let me show you something else whose existence we wouldnt imply form
the orbit of an atom and this is probably the most complex system in the
galaxy. I wouldnt go as far as saying the universe, maybe theres Klingons
out there! I dont know in addition to this so this is all made out of atoms
and you will say, Well, this is one hell of a lot of atoms so, sure, all hell
can break loose but, just look at this. This is a lot smaller and its all made
out of atoms and yet it has a lot of what the elephant is and the brain is and
certainly biology, go still smaller is a single cell organism. We still have alot of the characteristics of the elephant, the brain and its all made out of
atoms. We go still smaller and we get to a virus. Notice, were now on the
nanoscale of about a hundred nanometers and here is a virus and here we
cannot discuss this is the borderline between living and non-living matter. Is
it a life or is it just a very complex replicator? This is certainly happening
on the nanoscale. So you say, Well, sure, its biology, its complex and we
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know how complex it is. There is some quality that arises there that we
dont recognize in the atom and yet all of this is a combination of atoms, a
conglomeration of atoms put together in a complex way and then generating
mini matter but I would venture to say this is not just true form biology.
Look at this. Youll recognize this. Theres a lot of steel in there. And the
properties of steel are not determined on the scale of maybe a little atom but
they are determined on the nanoscale. You have to put a few atoms together
to make steel. The properties of this steel, whether its rust resistant,
flexibility, its strength, all this is determined on the nanoscale, not the atomic
scale, but already on the nanoscale.
Or look at this here, here is wood. Of course, this is dead matter but the
stability of wood, its resistance too, how it weathers, all of this, is
determined on the nanoscale, not on the atomic scale. Here is somethingelse, ceramics. If you look at ceramics, the crack resistance, its strength, its
flexibility, determined on the nanoscale, not on the atomic scale. But it is
the nanoscale that decides these material properties. So, macroscopic
material properties, whatever you look at - glass brick, T-shirts, bicycle
grease, whatever - is determined on the nanoscale. It is the first time we can
put atoms together to make something called interesting, something complex
which eventually determines the material properties on the very large scale.
Then, we say, Okay, fine, but this is very different from biology. Biology
is self assembled and this, well this is self assembled too. Were not taking
atoms and taking them under the microscope and putting atoms together and
making a brick out of it we just take
so self assembled. So, in this sense, its not that dissimilar and the first time
you can get something interesting, some complex material property or some
complex behavior is when you go up to the nanoscale and its actually very
much along the line of what a colleague of mine, Philip Anderson, once said,
Moore is different, Moore is not just the sum of the parts but its different.
Theres other, theres emerging properties coming out. There is something
happening there that we do not know how to describe yet. We may not beable to describe it. It may just be one rule after another. There may not just
be some brilliant law thats still to be uncovered. It may just be one rule
after another. But, coming back to this aspect, all this is self assembled and
its happening on the nanoscale.
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The nanoscale is also the scale where the discipline is nowadays and Ill give
an example from my metaphysics background. In the end of the last
century, sorry, game over. In the last century, before the last century, so in
the nineteenth century, we knew how to describe the single crystals and, at
the turn of the century, we were able to get X-ray pictures out of it and
nowadays we can actually move atoms around so this is a nanoscale at two
nanometers across so we are working on the nanoscale. In material science,
we know how to make silicon crystals, cut them into pieces do basic
lithography and working this out technologically on the nanoscale. The
chemists have gone somewhat the other way. The chemists have started out
with relatively simple molecules and they build up to more complex
molecules and, nowadays, are looking at how to assemble these complex
molecules into bigger entities. And heres, for example, something that
theyre working on and heres something called the nano mushroom where
you take molecules and you do a few (unintelligible) but youll get either orhydrogen bonds to make up entities that are on a bigger scale than the
individual molecule and that is on the nanoscale. And biology, too, came up
from species down to single cell organisms and, nowadays, ascribes the
properties and function of individual molecules and all of this happens at the
nanoscale.
The disciplines are talking to each other. The disciplines are learning each
others language which is often the most difficult part. Its not only in the
real world that language is a very strong boundary but also in the sciences.
We learn that similar kinds of mathematical methods can be used in the
different sciences and the boundaries between these sciences is actually the
most fertile ground for progress so the disciplinarity in our science is almost
anonymous and the interaction between chemistry and physics is one thats
very strong and were now building up interaction with biology which for
the last five years we havent done yet but there is very fertile ground.
So, if you talk about the nanoscale, you can come from different angles.
You can come from material science, biology, or from chemistry, or from
physics. With my background in physics, let me give you my perspective onit. I believe that the reason that we are nowadays so comfortable on the
nanoscale is actually this one. Im not sure whether youll recognize this.
Does anybody recognize this? This is the first transistor. This is the first
transistor as it was in 1947. Christmas Eve 1947. Christmas Eve 1947.
These people were working on Christmas Eve! And the size of this is about
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the size of an egg. Most of this is the holder. The actual bit is quite a bit
smaller but the whole thing is about as big as an egg.
So, this was in 1947 and here is what has happened since. This is the
itanium two chip and this thing has 220 million transistors and all of them
are working so, in roughly fifty, well sixty years, weve come from one
transistor to 220 million. In fact all of this, no most of this, is actually on the
nanoscale. I very much feel that this nanoscience nanotechnology is very
much furthered by the development in the silicon industry and the progress
is really enormous. This is a Moore plot which shows you the number of
transistors on a chip from one thousand, ten thousand up to one billion from
the 1970s to the year 2004. Oh, I extended it. This little thing doesnt exist
yet at the moment but you can see what its about.
Whats so impressive about this industry is that every eighteen months itincreases the number of transistors on the chip by a factor of two. So it
doubles every eighteen months and it has done this since the 1970s. Of
course, this is not a physical law but it has become a rule in the industry and
everybody is looking at this plot and tries to stay on it because if they dont
do it then their competitor will. So, implicitly, it became a law. So this is
the Moore plot. And, also, whats quite interesting is that every eighteen
months were making more transistors than we have ever made before
because a half plus a quarter plus an eighth. one plus a half plus a quarter
plus an eighth . So its enormous work this industry has achieved and
many of the features of these chips nowadays are only in the nanoscale. And
that Ill come back to.
But, before that, let me just point out once again how enormous the progress
of this industry has been and heres a comparison. Where would our cars be
if the progress in the car industry had been as fast as in the silicon industry?
What Im showing you here is a 1948 two door sedan, a car that the inventor
of the original transistor could have driven. It has four wheels, two
headlights etc. If you see the same car in 2006, it has four wheels, it has two
headlamps etc. If the progress in the car industry had been as rapid as in thesilicon industry then the car would weigh four grammes, it would have a
mileage of eighteen million miles to the gallon, it would have a speed of
twenty one million miles per hour, the trunk would have 410 cubic feet but
the most important part of this is that the cost would be only three dollars!
But it just demonstrates how incredible the process in this industry has been.
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So let me show you one of the, well, I shouldnt call it miracles but, in
terms of self assembly, one of the aspects of the silicon industry, that they
are growing now silicon crystals that are forty centimeters diameter, two
meters long and what is so amazing about it, after all I find that weve all
grown sugar crystals when we were kids but, nevertheless, in this crystal,
this is one crystal which means that if I take an atom down here and I count
1.3 million over here and I count 13.3 billion up here and another 6.4 billion,
its exact to an atom again. All of the atoms are exactly in the right place. I
mean its just strengthened my argument, this is self assembled. Were not
putting the atoms there. Mother Nature does this for us. This is almost a
miracle. These single crystals are then being sliced into these wafers and
then we make transistors out of them.
And heres one of the transistors. I show you this for a very special reason.
This is actually a picture that was taken, by now, almost ten years ago andvery hard to switch off arent they? So heres a transistor. I show this for
one particular reason. For one, as I say, this was ten years ago, the
experimental stage nowadays. This is the transistor size that we have in the
circuits and you see the length scale here, 60 nanometres so, so this is the
gate, oops, this is the gate so electrons are coming in here, now passing by
here and theyre going out there and you see theres a length scale here, 60
nanometres, so this is in the nanoscale. These transistors are nowadays on
the nanoscale and what I found most impressive about this picture is that, on
the same scale of which I see the whole device, I can see the individual
atoms. You probably cannot because its a little bit bright in here. We can
count the atoms from here to here as 382 so the scale on which you see the
whole device, we see the individual atoms. So, we people, we engineers,
particularly the engineers actually are very comfortable with dealing with
the nanoscale nowadays. This is most of what theyre doing.
There is another length scale in here that is the thickness of the silicon
dioxide, a thin insulating layer which is blown up here with of four atoms
thick. If you make it much thinner, then the electrons will actually quantum
mechanically through so we have quantum mechanics in our pockets. Soone cannot make them thinner than that so theres a limit here as why were
not quite down on this next scale in manufacturing . Were making billions
and billions of these on the nanoscale every day so the nanoscale is not
something foreign to engineering.
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Heres another one. This is, what I just showed you was in silicon, this is a
layer system made out of Gallium Aresnide, Aluminum Gallium Arsenide
which you really should look at thats just being two different semiconductor
levels. There we go, theres semiconductor level one and semiconductor
level two. The way this is being made is that they take a big vacuum vessel,
a big vessel, pump all of the gas out so that you dont have oxygen and
nitrogen anymore and then, then you load two ovens with semiconductor
number one and semiconductor number two and you evaporate it onto a
substrate which is a piece of semiconductor that you got by other means.
You can buy this.
So, theres a Gallium Arsenide substrate and you can evaporate
semiconductor one or semiconductor two onto it and here are these little
shutters, one thing on, one thing off etc, back and forth. In fact, when I
came to Bell which is now, I was working at Bell for twenty five years sothis was sometime in the seventies, this was still done by hand and what I
find absolutely amazing is that, by hand, you can grow a single layer of
semiconductor number one and then single layer of semiconductor number
two. So, you just stand there, operate this shutter and in about one second
you create one single atomic layer just by hand. So we already have our
hands on the nanoscale. Weve had them on the nano scale for quite a while.
But what the picture shows you is four layers, four layers of material number
one and four layers of material number two and this is of course on the
length scale of nanometers. What you can do with this and, as much as
silicon plays an important role in electronics Gallium Arsenide or even
Gallium Arsenide semiconductors play a role in, in the internet and
photonics or data transmission along glass fibers and these layers I just
showed you are essential for long distance transmission of light. So, what is
generated on the nanoscale is essential for our operation of the internet.
And heres a more complex one. This is Federico Capasso who has invented
something called the QCL laser, the quantum cascade laser, but the layers
that I showed you before are a little bit more complex and you create this
computer simulation and this laser has beautiful radiation patterns and theyare and will be more important in the future for sensing, remote sensing, of
environmental impact gases for example. So here, too, the nanoscale is
essential for the operation of the device. Now what I showed you is, these
layered structures and their impact on photonics, the word for long distance
communication via glass fibers. You can also use them for electronics, just
like you make these very thin electro layers in a silicon mosfet, a silicon
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transistor. You can also squeeze electrons between these white layers and
keep them out of the black layers. This is something I wont go into. You
can put a source and it rains, you can see the electrons coming in here and
going out there with a gate on top. So here is a transistor made out of
different materials and whats interesting about this one is the fastest and
quietest through this little world. In fact, its quite possible that quite a few
of you actually carry one of these little things in your pocket. This is called
a HEM transistor, high electrode mobility transistor and its very often the
first transistor in your cell phone because it, because its very quiet and very
fast which is what you want for a cellular telephone and theyre very often
also in, you see the receiving end of the antennas. So, again, the nanoscale
plays an important role.
So let me take these two dimensional systems and let me take this one stage
further and do this in a very superficial way but just to bring home howcomfortable we are, nowadays, operating on the nanoscale. Heres just an
example. Taking these sheets that we make by layer by layer growth of
different, of different semiconductors and you can break them up by
evaporating electrodes on top of the two dimensions and you see this scale is
a bar, a one micrometer bar and this is done with something called electron
beam lithography and by putting electric bias on there, we can crate little
puddles. So, there are two red puddles here, the red is painted in by me,
where this is a puddle that contains just one electron and this is a puddle that
contains one other electron and putting different voltages on, in fact, heres a
drawing and you see one electron sitting here and one electron sitting there
and the electrons have spin and, without going into the details of all of this,
we are now not just able to do electron ESR, electron spin resonance, with
individual electrons and we can operate with individual electrons and this is
a precursor to which I will come back to later in the afternoon for quantum
continuity. But we have become very comfortable with operating on
individual electrons, not only on their charge but even on their spin.
Let me show you another example, so this is really hands on quantum
mechanics. Heres another way of taking this two dimensional system thatwe have created and making smaller entities out of it by growing, for
example here, Indium Arsenide on top of Gallium Arsenide and these have
slightly different lattice constants so the atoms are arranged in a slightly
different way and, therefore, they grow these little hillocks. This is self
assembled. This is not something were doing from top down. This is
coming from the bottom up. It can create these little hillocks here so these
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are little quantum dots. You see them here and, again, a little here. They
create quantum dots on the nano scale and, in fact, this has been researched
quite extensively. We are thinking this might be a better source for
semiconductor lasers. Again, technology on the nano scale that is already
being pursued. Here is quantum dots made by chemistry and Im not much
of a chemist and, therefore, Im showing you that it is just being done in a
typical chemistry way which is in glass test tubes which is different from
what were using. Its actually a very cheap way of making quantum dots
and these are dots that in this case have the diameter of eight nanometres,
made out of semiconductor. I think this is (unintelligible) sulphide.
You see the individual atoms, the picture is taken of the individual atoms
and whats so fantastic about it, its just like your atom, you have the
different weight functions, now you have the different weight functions in
this sphere and the sphere acts like a mu atom, an atom contains electrons
and the energy of these electrons will depend on their size. So if you make avery small one, then their energy is high and if you make a big ball then the
energy is lower. What this leads to is, if you can make, if you just sort out
the right quantum dot, in actuality if you make small quantum dots they look
blue and big quantum dots, they look red. And, therefore, this property of
what is the color of it, does not depend on what the material is but what the
size is. Right? The material is always the same but by changing the size of
the material we actually change the property. In this case its what is its
color. So you ask what is this good for?
There are companies out there who are already selling this. This, by the way,
was invented by one of my colleagues Bruce who is now also at Colombia.
The companies out there who are selling it, its being used in biology to
encoat these materials, these quantum dots with antibodies so they go after a
particular protein. You can take different sized quantum dots, coat them
with different antibodies and the blue ones go to one protein, the green ones
go to another protein and, therefore, if you are now sampling biological
materials, different proteins will light up in a different color. This is of
course something that we can also do with dyes created by chemical means,
where the different colors are created by different site groups, but theadvantage of theses kind of dyes is that they are very robust, you can make
any color you want by just changing the size of it, they are very small,
typically non-toxic, thats of course something that is on the mind of very
many people now and they have many applications. So here is something
that comes out of nanotechnology, if you want, relatively easily, it has an
impact on biology immediately and maybe, maybe at some point beings as
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well. In fact, here is a quantum dot that with a coating of a certain antibody
that particularly accumulates in a liver and you see theres a, in a rat, you see
this. So in medical research, you see that it is already playing a role. So
again nanotechnology in medicine is already playing a role.
The spin of the electron is an important part of the electron that in todays
electronics is not being used as they are only looking at the charge, but there
are ways to look at the spin of the electron and there are projects that
envision that using the spin rather than the charge will allow us to go to
smaller device sizes at some point in the future. This is very much at the
forefront of research in meta physics.
So in terms of this layer structure I had talked to you most about applications
and let me just bring up one thing that is err, that I am associated with and
that is these layer structures are not only good for applications which theycertainly are in the optic and electronic industry, but if you make a sheet of
these electrons and put a very high magnetic field on it, then something very
strange is happening. The electron falls apart. What is happening if you
measure the charge of the electron afterwards the charge looks like it is
about a one third of the electronic charge so this is happening at very low
temperatures very close to absolute zero and very high magnetic fields to the
sense that if you were to take the transistor that is in your cell phone, you
would cool it down to almost absolute zero and put it in a very high
magnetic field, the electron cracks up.
Now that is very astonishing, because our colleagues at Columbia and also I
suppose here that in high energy have used the electrons and bombarded
them into anything and the electrons never break up. So electrons are
elementary particles to all intents and purposes and here under these
conditions actually they seem to break up and in fact this is what I will talk
more about this afternoon in my colloquial. This is actually called the Horne
effect and actually as some very interesting, even projected applications now
which just a few years back we wouldnt have thought, we would have
thought just a very interesting fundamental physics result but it seems tohave applications.
So if you can come this afternoon. I have actually a new graph here, but let
me see how much time do I have? I have 10 minutes, well actually I have
two hours but I do not want to hold you that long. So let me perhaps skip
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this new graph as you can see it as it is and Ill show you a bit more about
this, this afternoon.
Okay, so on the nanosphere, coming back to the nanosphere, well this was
all nanosphere but the matter, the matter assembles itself in ways in which it
wouldnt at the macroscopic scale, here is a few examples of it. Here is
some gold, gold layers on the nanoscale that look, look like they are
assembled in the way of pennies, This is alumina that has assembled itself in
a hexagonal way, here lead sulphite quantum dots have assembled
themselves in this hexagonal fashion. Zinc oxide, on a very small scale
forms these rings here and also these spirals here, all of this is happening on
the nanoscale. And what we know of this nowadays and we can see with an
electron microscope wondering if there is an application for it and I think
that this is still something to be found out. I think the poster child of this is
probably carbon, so here is carbon which we know as having twomodifications, one is diamond and the other is graphite, and graphite is of
course so interesting, well technologically important because there are sheets
of carbon that very easily glide against each other because in vertical
direction they are not covalently bonded, just in the other direction, the Z
direction, so they glide very easily, this is why we make grease out of them,
lubricants out of them, and the other one is diamonds which has other
applications
Then of course in the eighties we discovered Lucky Balls which I think was
a very, very exciting discovery for two reasons, I mean many reasons. I give
you two in addition to those that you may already think. Number one, I think
had you told people a few years before in scientific circles oh and by the
way carbon can also make soccer balls you would have been laughed out of
the room. This actually exists that Mother Nature would make something
like this. I think most of us wouldnt have left the room, The second thing is
that this is not something that we are making industrially, it is something
that was around through the aeons, in fact this stuff is in meteorites. So it has
been around all the time and we just didnt find it. So it took until the end of
the second millennium after Christ for humanity to find out that this isanother configuration of carbon. One of the interesting aspects about all of
this.
The more recently in about 1990 in Lima, found again using an electron
microscope, a nanotube that is really a rolled up carbon sheet and what is
interesting about is just remember what I told you before about the size of
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the material determines its color, here the property of the material is
determined by which way I roll up the graphite sheet. If I take the graphite
sheet and I roll it up in this way or I roll it up in this way it has a different
property. You see two graphite sheets from the side here, this is one that is
rolled up in this way and this is one that is rolled up this way. This is a
metal, this is a semi-conductor and it only depends on which way you roll up
the material, so again on the nanoscale, the way properties evolve depends
very critically in small variations in parameters.
We can grow nano tubes nowadays, almost like grass, this here is a picture
and we can make them extraordinarily long. This is, in fact, a result from
Phillip Kim, who is at Colombia, you see nanotubes growing from a catalyst
and all the way across you see nanotubes almost four centimeters long, so
nanotubes they are about 1 nanometre diameter but four centimeters long. In
fact, the reason that they are only four centimeters long is that is how longhis equipment was, he had to stop there otherwise they would have fallen off
the wall. So, in principle, you can grow these things longer, in fact much
longer than that. These tubes are already used in, in fact they have been
contemplated for their mechanical properties, here is a string made out of
nanotubes, here is a fabric actually woven out of nanotubes and even
artificial muscles are being considered made out of nanotubes in such an
environment. And of the, well most of the far off projection of using
nanotubes is a space elevator, where at some point if you have satellites,
probably in a geo-synchronous satellite standing out there, rather than
shooting a rocket up we actually have an elevator, using a string up, you can
pull up material and have the same command of material coming back down.
What is interesting is if you ever could make this, if you ever could make
this you cannot make it out of steel, because steel is too heavy and it would
just rip under its own weight. So if we ever can make this we need materials
such as nanotubes which is easier. You would need a blown up version to
make a space elevator and people are taking us quite seriously. And see if
we could make a rolled up tape of something like this if we are ever to make
a space elevator, so nanotubes have great implication for mechanics but not
only this they also have great implications for electronics.
I showed you this one before, this is a transistor 60 nanomentres and 180
atoms from one side to the other. This is a more recent one by Intel, 30
nanometres length, see the picture now, 20 nanometres, which is still
something in the future, its not yet in your laptop, but look at the size of this
nanotube compared to these transistors, this is an individual nanotube made
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of carbon and look how small it is, and then what people are thinking is that
we cannot use nanotubes for electronics. Here you see a nanotube lying
across four contacts thats being measured and people have made transistors
out of this. This is from the Hughes Group and here we see one nanometer,
sorry one nanotube, lying across two contacts. Here is another one from
IBM. This is actually a bi-polar, the other one is piezo in the back here you
see a nanotube lying across and this is just a schematic, okay, so one can
make transistors out of nanotubes and, interestingly enough, their properties
are better than those of silicon.
So in fact in the United States, Intel are taking this very seriously and are
supporting research in this direction, where the nanotube could at some point
replace silicon in the channel of fets.
The trouble of course is that you do not know how to put the nanotubes intothe right place first of all you need a lot of them in parallel to get the
conductor that we want and, second, how do we actually put them there?
We have to grow them so chemists are trying to figure out how do we grow
nanotubes in exactly the right place, and we are far from it. But the
properties of the individual nanotube are now very similar to those of silicon
so its very promising.
Ah, here is actually something that we did, just a next step this is something
that we did in the Nanocentre. We took a nanotube, this is a nanotube and
we cut it open and we placed in this opening with one individual molecule.
We were able to place one individual molecule in there and in this case this
is a metallic and this is a metallic nanotube, so this is a contact and this is a
contact and then this one molecule acts, acted as a transistor, just one
molecule acting as a transistor.
- Video disrupted -
Let me tell you about my immense amazement about this one gizmo that I
think that nowadays I think that the people here will all be familiar with but Ifound it just an incredible, incredible leap of confidence that at some point
was made, in fact by Gurt Biddich who is a, with who I studied together at
the University of Frankfurt. We were on the same row, next to each other,
What Gurt did, or rather though of, this incredible thought he sprung. If you
take two objects and you put them close to each other ever so gently, closer
and closer and closer, at some point just when they are touching, the
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touching is just one atom from the left and one atom from the right. And
this is another one of these examples where probably a few years before
people would have said, how are you going to look how this happens?
Thats not something that you would theoretically think about, not really the
way you want to do it. Yes you can. Now only using one hundredth, so again
using my hair and if you think of making anything, if you think of making a
sharp tip on the nanoscale, on a scale where the atoms are as big as soccer
balls, then probably the sharpest thing that you can make is a (unintelligible)
like that again. You may recognize this one so if I make this out of atoms
then it may look like this and there is always one atom that is sticking out
the most and here is the top and I see one atom that is sticking out and if I
take this and move it along the hair I can probe, I can see the atoms. This
actually works, and yes some of the students here will say I have one of
these in my lab. I push the buttons and it comes out. I tell you, in 1983, I
think this was not a possibility. You can do this very confidently now.Really its nothing else more than just a gramophone, a very fine
gramophone.
Let me just skip through the movie thing and not only can you look at things
but you can move atoms around. Here you see the surface of copper and I
think that its actually carbon monoxide that sitting up there, so think of it as
an atom. Its just a very small molecule and you see that someone has
already done the job on it, and if you look 6 hours later, 12 hours later, 24
hours later you get what is called the quantum coral which is circles of
copper and carbon monoxide based in a circle around it and my point is that
the feed itself made putting this together mind-boggling. What I find most
mind-boggling is that you see these waves and these are just the electron
waves as we know them in quantum mechanics and you can actually see
this. Again is something that wasnt obvious at all that you could actually
dive in and observe on the nanoscale things in such detail. That is once you
have colored it in, it looks even more gorgeous than it does just from the
electron microscope.
Let me come back to the last few minutes, a major subject of my lecture, Itold you a lot about the nanoscale and things like quantum dots and three
dimensional electrons and finally about the nanotube and that it has big
implications for mechanics and probably electronics but in a certain sense
along the lines of John Hopkins statement but its boring, this is still after
all relatively, well very boring. We walk along a nanotube and all you see is
carbon atoms, carbon atoms and put you in any place and you look around
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and think this looks like a lost place and on the same scale if you put DNA
which is the same scale, DNA is really complex, right? Obviously, the
information of life is written into it, the local environment is very different
as you go along, so this is interesting in that sense whereas this is very
boring and what DNA can make for example are things like us, it makes
them very cheaply. Heres a biological product, what is it, fresh baby
artichokes, so artichokes, just done by Mother Nature by self assembly. This
is how we assemble things, this is top down, a different pattern I would think
and it is a very different process. So whats missing sort of in electronics,
what we still havent figured out how to do is how to grow our cell phones
on trees. If you had a laptop that was about to die, you would sprout a
flower take the seeds, put them in the ground and in the next week, harvest
the laptop! Mother Nature does just that. So why not? You say its not
possible. This maybe asking a little bit too much, you want to grow a whole
laptop? Okay, fine, I give you a cell phone, although cell phones areactually more complicated than your laptops are. So lets take just a chip,
can we grow a chip on a tree? Well even a circuit, I just give you a memory
cell. Okay, how about we really put it down, can I make one transistor, can I
grow just one transistor on a tree? Yep, there it is. Alright? This is a model
that was assembled by my colleague Colin Marples that acts a transistor,
electrons are coming in here, going out there and if I apply a voltage to this
thing it would drop the electron flow. This is grown on a tree, this is a
transistor made by Mother Nature made by self assembly. All identical up
to the last atom, it probably cost about a buck to assemble 43 of them so
silicon, eat you heart out, you are so proud that it is 0.001 cents per transistor
that is a few orders of magnitude cheaper. So this is a transistor, so lets
make wires. Well wires, I can grow them on trees. I showed you all a wire
that is 4cm long, it is more conductive than copper and it is stronger than
steel. What else do you want? So silicon, eat your heart out.
Now of course you know thats not the problem. The crux of the matter is
not to make the switches, the crux of the matter is not to make the wires, the
crux is the viability. It is not how to make the components it is how to put
the stuff together and, in a sense, to put this aside I find the expressionsilicon industry a misnomer. It really should be called lithography industry
except you would have such a hard time pronouncing. That is the defining,
this is the defining technology, we could probably use other semi
conductors, lots of other semi conductors, had we put as much effort into
gallium arsenide it probably would be as far as silicon, the real thing is how
to put the stuff together, its the (unintelligible)
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Right and there is only two ways of putting things together, complex things
on earth, one is (unintelligible) where we are walking round in masks like
Halloween and finally come up with devices like this. Mother Nature does it
rather differently. Here is a Sequoia tree, here is scene of a sequoia tree and
you would wait about 200 years to develop another tree. It is a very different
way of assembling things. So you could say, okay, we are making great
progress over here, lets just leave it to biology. Self assembly, this is a
fantastic way of assembling things, all hands off, just leave it to biology. I
believe that this is not so. There are big ethical reasons. I think in particular
when it comes to electronics for doing data processing and so on, leaving
that to biology would create lots of ethical reasons. You wouldnt want your
dog to be smarter than you, well some people maybe. So I think fiddling
around with the genome in this respect is probably something that we would
have big difficulties with, well thats one, there is another one.
Biological data processors in my mind are made of very lousy components
and as much as I am sitting here with electrical engineers you may actually
agree with me that the neuron is an awkward, an awkward object. It
transmits signals by basically a bucket brigade, handing it down and thereby
eventually telling the end that something has happened at the beginning.
The speed is about 10 100metres per second, whereas we are typically
transmitting at the speed of light and the switching process is awkward
where a few dozen or hundreds of little vesicles have to cross some cleft,
some synaptic cleft come to the other side and transmit the signal. So we
should be able to do better than that. You may consider this to be heresy, but
I am not sure because when we concentrate on something, some particular
priorities, we are doing very well. We can argue whether we should also be
able to do better in terms of data processing. And by the way this very
simplistic calculation, although I dont think it is that much or that long. Our
brain has 1015
synapses so it does about 1017
operations per second,
something like that, you can argue a factor of ten or even a hundred with me.
Your Pentium chip is about the same. You may wonder about how you canthink about the origin of the universe whereas my Pentium chip in my laptop
can barely run PowerPoint and it results in a poor usage of these transistors
so architecture and software is something that is very important. So how can
we go about it if we dont use biology? I think that there is at least two
approaches. One is to use biological materials in another context. So this is
not biology but use of biologically made materials and let me show you one
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such example. This is using DNA as a smart molecule. This is actually
artificial DNA. This is not coming out of any cell and not protected by any
DNA exemplars these days. This is actually out of Max Seaman down at
NYU, just about a subway ride from us. He looks at the DNA as a molecule
and the addresses in it, and if you address it right you take the sequencer and
you make a molecule out of it thinking about how it should assemble. We
are just putting the right sequence into it and then pouring it into a glass, you
get for example, this is not a typical double stranded DNA, you get this knot
out of it. Here is another knot and here is a third knot, this is very important
because it is programs, right, he programs it in he doesnt twist it around, he
pours it in and these knots come out by themselves. This is a geometry that
is created in a big machine but in a linear version and then the thing
assembles itself in this knot. The most complex structure here is this Q
made out of DNA programmed on the outside and then self assembled. It is
all hands off.
Here is another example. These are actually sheets made out of DNA.
Strangely enough, by putting these cross connectors on to it you can make
sheets out of it, In the end you pour it in, you can make a two dimensional
sheet. You can program certain spots along the sheet that is just where you
fix and bolt nanoclusters and you see here that the green thing is the sheet of
DNA and the nanoclusters are sticking up there. The thought behind that is
that it quickly, thats all on the nanoscale, that quickly a two dimensional
scaffolding in order to build up later put circuits on top of it, self assembly.
Here is probably the most ambitious of it. Here is work done by Uri Simone
At the Technium in Israel where he wants to make electronic circuits self
assembly. So here are the edges of the circuit, this is gold and there is a
single strand of DNA attached to it that would have all different addresses.
Then he pours in the complement. So this is our DNA that has two
complementary addresses and they find their way. This is one that is
programmed for example. This is programmed to go form here to here and
eventually it finds it way. It makes its pattern which is preprogrammed but it
has assembled itself, you can even be thinking even and I am going to showyou in a second, of putting devices down because you have addresses on the
DNA onto which you can place devices and eventually he ends up with a
circuit that is self assembled.
Here is an example of it, you can make a nanowire, it goes to an address
here and an address here, the DNA across makes a wire out of it and you can
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even place a carbon nanotube transistor, a carbon nanotube that acts as a
transistor, so in this way you can make a transistor self assembled using
DNA that finds its place and using a carbon nanotube that finds its way.
Here is a picture of it. Its a very, very lousy transistor, it really has not a lot
to speak of, but it is self assembled. It assembled itself by just programming
the position in, in the first place. So thats number one.
Number two is to start from square one and that would be for example self
assembly of the molecules and this does not have a name. It is just
chemistry and as much as I flunked chemistry as a student I am in deep
admiration of chemists nowadays. My colleague Colin Marple, father of the
young guy we saw earlier said, tell me what you want and Ill make it.
Now hes young and probably a little bit overestimating his wizardry, but
there is a lot of truth to it. Chemists can do extraordinary things. Ill just
show you some other structures that we dont make and then discover them,but they really design them to be this way. So chemistry is one, but if you go
beyond chemistry, they call this super molecular chemistry.
You now take molecules and assemble them into bigger structures. There is
one and its most amazing. There is a chain and there is one molecule
walking along it, just walking along it and actually creating a product that is
then attached to the chain so its like a molecule walking along another
molecule. So, if you combine the super molecular chemistry that can play
with molecules and make structures that are not also static but also dynamic
then you add to this the atomic source microscope being able to measure
forces on very small scales, being able to affect things on very small scales,
which I would call super molecular physics. If you put these two together,
this is what is really in my mind at the heart of nanoscience.
Therefore, self assembly is an essential challenge to nanoscience, but you
need to learn the simple rules from biology and apply them to non-biological
studies. You have to learn the rule of the molecule-molecule game and not
only in biology but also in the non-biological sciences. You have to learn
how to make copies and templates and all of the other things that biologycan do so well and if we explore this we are not going to (unintelligible)
ambient pressure (unintelligible) we can do it on the surface of material for
example. So if you look particularly at the challenge with regard to
electronics, they must be simple non-biological substances that are self-
assembled and the electric properties are essential. Nature is largely
ignorant of electronics, all of the electronic properties, so called electronic
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properties going on all over our brain and our body are largely ionic. They
are not electronic, we need to keep our eye on electronic properties. So at
some point in the future we should be able to combine silicon technology,
which is wonderful and will not just sort of go away at some point, actually
it may stay forever. The silicon technology will allow at its edges the
intelligence is in the process, but at the edges you should be able to assemble
ready made molecular memory cells that the silicon processor will actually
assemble out of the liquid. So that the self assembled aspect of this
technology will start at the edges and perhaps over time would creep in. So,
with all this, why not? Why shouldnt we at some point be able grow a new
laptop or a cell phone on a tree? Thanks very much.
Floor open to questions.
Prof. Strmer: I was hoping for enlightening discussion so we have, well wehave another hour almost so please do.
Question: Please sir, what is your opinion about teaching of nanoscience or
nanotechnology in university. Please sir what do you think about the
structure of teaching or study of nanoscience and nanotechnology?
Prof. Strmer: That is a very good question. Thanks very much. I think you
all heard the question, right?
The question was about education in nanoscience at university
I think as I showed you before that I, where nanoscience, where the
disciplines meet. I think you also have to teach this between disciplines.
Nanoscience is not something that can be evolved by physicists, not
something that can be evolved by chemists, not by biologists and not by
electrical engineers or mechanical engineers, but we have to all come
together. This is very hard to do. I cannot judge how hard it would be at your
university but it is hard at our university. I think that in general, probably inmost education systems in a sense we are stuck with the disciplines as we
created them last, last century and before that. So when we split up natural
sciences into chemistry and physics and biology and the engineering
sciences yet in another place.
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And in another scheme all of this is coming together, our students move to
have an exposure to all of this, to much of this in order to be effective in
sciences and this is very hard to achieve between departments in
universities. And I dont think that there is a golden way of doing it. It is
something that we have to create from the bottom up, just as much as we are
thinking about bottom up assembly we have to create it from the bottom up.
It is, as very often the case, you need a few individuals that are excited about
something to just go ahead and do it. At Columbia there are a few lecturers
now that are co-taught between physicists and chemists, which is a good
start. We have also a mechanical engineer who is doing this with a bio-
physicist sharing a lecture. This is baby steps but I think eventually we have
to, we have to be able to teach this on a much broader scale and I am not
sure how to do it. The best, I believe is that if there is a set of individuals
that believe in this and then just create their own curriculum. I find that the
students are very willing followers. In fact you could call it the other wayaround. The students are coming to ask us, How am I going to do this? We
have, I think, I remember meetings we have in the Nanocentre, where
chemists are coming over and saying, Professor Strmer, and by the way
they all call me Horst, Whats the physics course that I should take so that I
get a good insight into chemistry? So the chemists are coming to us and I
hope the physicists are coming to the chemists. So it its from the bottom
up, it will not be from the administration down. But it is the young people
who are requesting this and well have to find ways to respond to that and
its true it was in the present departmental structures at the university, so
well have to overcome it.
Speaker: Next?
Prof. Strmer: I promise the next time Ill be a little bit shorter!
Question: What about Carbon nanotube transistors?
Prof Strmer: Carbon nanotube transistors, yes?
Question: By much how are they better than silicon, do you think it can be
better..? PH Speaks over.
Prof Strmer: They have sharper (unintelligible) so for a given voltage they
would have less leakage from them. I do not know, I do not have the number
in my head. But they are significantly better that IBM has started a
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engineering group actually working on carbon nanotubes, so this is an effort
of about five or six people so they are taking it very seriously. In fact there is
even an Intel group looking into this. But let me point out again, I dont
know who asked that, but let me point out again, the important aspect of this
or the difficult aspect of this is not how you make this stuff, the difficult
aspect is how to place these carbon nanotubes where you want them. You
have a great way of putting a transistor where I want it, by using
photolithography, we have no great way to put a carbon nanotube
someplace. Nowadays we are using an atomic force microscope and slowly
nudging them into place. This is not a large scale manufacturing
chronology, you have to find ways how to do this and I am not sure that we
will. They may be incompatible with circuits, its not clear whether we can.
But then again we wouldnt have thought there was a carbon nanotube in the
first place, so who knows?
Any questions?
Question: Do you think that about the extrapolation of Moores law
(unintelligible) reach atomic size?
Prof Strmer: Yes, that is a very good question. The question is about the
extrapolation of Moores law . Let me tell you a little story about it, its a
short story.
I go to a conference every two years, sometimes every three years, which is
called the future of, its not silicon technologies, its called, well lets call it
the future of silicon. And about ten years ago I was invited to chair a round
table discussion about the future of silicon, more than ten years, fifteen years
ago. You get the usual discussion, everybody is saying, well giving their
own opinion about it, it was not clear how much progress was being made at
that point so I thought instead of having a panel we just go into vote. So we
had about 50 people there and we were voting, when is silicon going to run
out of steam. Well it turns out it was about 5 years from now. We had the
same conference again last year. I wasnt there but my colleague took thepoll. Guess what? Five years from now. So this is now fifteen years in
between, but I think the arguments are getting stronger and stronger that
about, well I would think no more than ten years from now probably. I
mean there is good reason to believe that ten years from now, its hard. But
again, engineers and technologies have come around to overcome so many
revolutions, in the 70s who would have thought that a micron would now be
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20 nanometres. Its incredible so I wouldnt venture to say that it is not, but
Ill venture to say one thing, it will stop.
There is a question back there. If you just say it, I can repeat it.
Question: Horst can you pretend again that you were a first year post-doc,
which topic would you pick now?
Prof. Strmer: If I were a first year..
Question: a first year post doc in condensed matter of training
Prof Strmer: If I were a first year condensed matter post doc, which topic
would I pick?
I have admission to make. For my last, of my last three graduate students,
one went to Cornell and worked with carbon nanotubes, she is now a
professor at Penn State, The second one went to Illinois became a bio-
physicist and the third one is just coming back from a trip to Berkeley and
tells me that she has an offer to become a bio-physicist.. So I am not sure
what this is telling you, but my wife is telling me that I am a lousy teacher.
But I think that is whats happening and I dont discourage my students.
Never mind bio-physics, I think its the inter-disciplinarity. I look very
much as a condensed matter physicist. I look very much that I have as least
as much connection to the chemistry department as I have to my high energy
physicists. What we are really working on nowadays and I am convinced it
is working on the nanoscale and what my chemists are talking to me about is
very much what I am talking about. So I believe inter-disciplinarity is really
the order of the day. So if I was a post doc condensed matter physicist then I
would go and do something that is at the border of something else, which for
example means that I would do bio-physics, working perhaps with a group
that does condensed matter chemistry, materials science. I think its the
boundaries where the excitement is and where we will be the future. It will
have an impact on science, on technology no doubt, but it will also have animpact on teaching. I think it will a huge impact on how the departments for
arts and sciences and engineers will be put together. I believe in ten years it
will not look the same anymore. It was a long answer and a little bit evasive,
but okay, right bio.. hyphenated physics!
Question.
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Question: Yes I am from the mechanical department
(unintelligible)(unintelligible)
Prof Strmer: You say, let me see whether I can re-cast the question because
there is a lot of room there. You are saying that there is lots of talk about
nanoscience and err, but its very hard to implement a lot of it.
I agree with you. I am of two minds on this. The one is I agree with you that
the word nano, in many cases, is very much hyped, its over hyped.
Everybody thinks, even government thinks and looks into whether they are
falling behind in nanoscience, the funding agencies listen up, if you do not
have the word nano in your next proposal then you do not get funded. But I
think that this is really unfortunate. That does not say that nano itself really
does have a place in the world or in the world of science. I believe that, Istrongly believe that nanoscience will have a huge impact and, therefore, we
have to go ahead with it. We have to pursue it. If it is in an area where there
is lots of hype it is ours, particularly the most senior peoples job to put
things in perspective. So if you make a connection with the already existing
nanoscience or what you call it or the technology that is out there that is
nano or chemistry that is nano and otherwise but just stonily pursue it. I
dont think it is so that all of nano is hyped, certainly not .
(Video disrupted)
Its an exciting time, a very exciting time. At some point you will look back
to the late 90s of the last century and all of this started up.
There is a question back there, Oh sorry here, yes please.
Question: You mentioned the United States, what about here, is there a good
support to continue this research in Europe or how you say?
Prof Strmer: Is there good support for research in the United States or inEurope?
Question: Europe in comparison with the United States
Prof Strmer: How does research funding compare between Europe and the
United States are you asking that?
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Question: What is the background, the environment to nanoscience?
Prof Strmer: Oh, oh particularly for nano. Actually I feel that it is very
good. On the scale of things, I mean first of all you have to look at research
funding in general. We scientists are always complaining that we are not
getting enough and the administration always says that we are getting too
much. So I think that there is healthy competition and we have to keep it up
on both sides, it makes us honest in a way. So I would think that the funding
in nano is actually very good on the scale of things, now everybody would
like to have more money to build the next new submarine or to build the
next x-ray satellite or to pursue condensed molecular chemistry or whatever
but I think that scale actually nano is funded very well. It has been funded
very well in the United States over time and I say that if you dont have the
word nano in your proposal then you wont get funded which is animplication of that, unfortunately. I think actually in Europe from what I
understand, nano is funded similarly well, the word nano is something that
applies to all of these funding agencies, the world inter disciplinarity fund
and as much again that much of this hype is fortunate, so we are all being
funded relatively well. I can tell you many stories of people who were under
funded but I listen to other colleagues who have gone away from nano and
their stories are worse. So I would think that funding for nano in the United
States and Europe is good compared to general science funding. I think we
should have more science funding in general. I think that this is a way to
solve a lot of our difficulties but I think on a relative scale. I think its well
and comparable between Europe and the United States.
There was a question there.
Question: Part of this business is nano problems start eight years ago, this
construction of nanostructures and nanobodies started at (unintelligible) in
the States and then ended up at (unintelligible) in Germany. We know the
results of this nanotechnology ceramics parts for the space shuttle for
example. Now the time is looking like drawing at hand for the materialresearch and they try to switch it to the biology and medicine. How you see
the progress in this field? Do you think you can wait such tremendous
progress like material research?
Prof Strmer: Well I do not believe that nano is at the end of its road in
material science. I really dont believe. I mean as much as you pointed out
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ceramics, I think there are many other materials. Look, I deeply believe and
I dont think that you would disagree, macroscopic material properties
anything surrounding that, is interpreted on the nano scale and if you find
ways of modifying that on the nano scale we have huge margins on the
macroscopic scale to change material sciences. I think, I think weve just
skimmed the cream so far. Its the easy low hanging fruits that we have so
far. I do not see the end of material science at all. It will get harder Im
sure. Right, I know thats what the whole overhanging fruit. I do not
believe that we wont make progress by combining mechanic and transport
structures, getting combined improvement where we get very strong
materials with still high electronic transportation properties. I dont see that
at all. I just think its going to get harder as it always does in the sciences as
I think mydiploma in Frankfurt always said, If it were easy, it would be
dull. Along the lines of biology, I strongly believe that, that nano will have
a big impact on biology and vice versa and I dont even look at it as one orthe other. I would think that its biologists and chemists and mechanical
engineers and physicists coming together and tackling, tackling questions in
biology that the biologists by themselves cannot do, that the physicists
couldnt tackle. You need all of this input so I, I believe that nanoscience
has a great future in biology. Right, its the right length scale, its a very
interesting problem set. Its, we can address it in the condensed metaphysics
community, in the chemistry community, in the biology community and
theres a follow up question. Go ahead.
Question: May I interrupt you? My question was this. You in the States
started with nanotechnology twenty years before Europe because you started
in the early eighties. Now we find that nanotechnology would provide an
application now because the Europe Union paid the money for this and we
said, Now. Look they said, They have invented this before already.
They said, Space shuttle technology already uses nanotechnology and you
have experience also in the bio. We start now reaching up their
nanotechnology but the migration was a little bit to, to application, to the
biology because you already have twenty to fifteen years before so this was
why I asked.
Prof Strmer: So youre saying in material science we see already
applications and what, since all of this started twenty years ago, wheres the
applications in biology, is that your question?
Audience: Yes
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Prof Strmer: Wheres the impact on biology? Well again, you saw the
example of quantum nano dots that are used in biology.
Theres an application. These nano dots are being used in other settings, for
example you have specific absorptions that are possibly of interest for
treatment of individual cells that absorb a particular energy at a particular
frequency so I think were just at the beginning of it. Look, twenty years is
not that long nowadays. I mean twenty years of research until you actually
get into a clinical setting is not a long time.
Speaker: I hope there is a question in the upper room.
Prof Strmer: Ah!
Speaker: So Ill try to switch over there.
Prof Strmer: Sir, sir, we do not hear you. We have to switch on your
microphone.
Question: Good morning, can you hear me now?
Prof Strmer: Can you speak a little bit louder?
Question: Louder than this? This is a very basic question but, firstly, I need
an answer. Do you hear me?
Prof Strmer: Sorry I missed it.
Speaker: You have to speak up. Speak loudly.
Question: Louder than this?
Prof Strmer: Okay, its okay.
Question: This is very basic question. I had a chance to work during my
Bachelors study on the basics of nanoscience. Now the problem was that it
was very difficult to touch the basic concepts. In order to learn how to apply
the concepts, you must know what are the concepts and it involves studying
basic solid state physics and I also I found that all the roads lead to quantum
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mechanics in the end. For an electrical engineer, its a little bit difficult to
get acquainted with all the things in a deep way and there are some basic
questions that I wont mention now and it took me to three students in
Prague just to find the answer. Of course, in the end, I did struggle. So,
from you, I have the question that how a student can get well acquainted
with the principles and applications of nanoscience in a good time, in finite
time, because there are other subjects which also must be tackled but can
you tell us the short way how an inquisitive student can make it?
Speaker: Your question is clear.
Audience: Thank you
Prof Strmer: I appreciate that it was a simple question and it all came
through. Again, I mean we have mentioned before how are you going toteach nanoscience which Im trying to look at you when I think theres
probably a camera there I think a question very similar was raised before.
How do you teach nanoscience and are we going to teach the next generation
of students and how do we do it? I think your question is along this line and,
as I said before, I do not think I have a kings pass and I think youre a very
good example of showing us that its the students who are telling us what we
have to do. It will not come down from the administration about how
theyre going to teach nanoscience until students are coming to our office
and asking exactly the kind of question that you are asking and well have
to I do not have a kings pass on how to do this. If you ask specifically, I
mean if you were to ask specifically and came to my office and asked how
do I, how do I get into quantum mechanics, what course should I take in
order to understand a little bit of quantum mechanics, the ones that I need for
an electrical engineer, I would be able to give you advice and say, Take the
course of Professor XYZ because I think he treats it in a way that is
appropriate for what you want to get out of it, but I do not have a general
work study. I cannot tell you take the nanoscience curriculum at Columbia.
We do not have it. I think, in a sense, it is very good that you ask this
question because there is a professor sitting in this audience and it will havethe impact to hear from you as one individual as to where you want to go
and what people more senior have to do in the future in order to educate it
the way you want to educate it and you told them already what is out there.
Question: You mentioned that Moore is different. Is there out there
somewhere some basic nanophysics laws which emerge on the microscopic
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functions and, more to the previous question, do you hope that nano
(unintelligible)_
Prof Strmer: All those are excellent questions. I do not have the answer. I
think that this is, well, okay, let me repeat the question if I can. The
question is that I brought up Moore is different and the reason that youre
asking me the question is where are we on that scale, how different is it and
where are the nanoscience laws? And Im afraid to tell you, we dont know
but Im happy to tell you, we want to know and we want to figure out, and I
think, let me put it this way, I think this is at the heart if nanoscience, this is
exactly what we need to figure out, this is exactly the challenge I think of
this century in this area. You asked for what are the laws of the nanoscale,
we dont know. We dont know and its not clear. As I said before, its not
clear whether there are laws. It may be just one rule after the other. Theres
this rule and this rule and if you do that then you get that. Right, we may beat the end of the laws, at least on this field. Im not saying at the end of
science but we may be at the end of laws. There may be not a
(unintelligible) equation, there may be not another equation, just rule after
rule after rule which sounds non-satisfactory. Course of all, I may be wrong
and there may be really laws which we havent discovered yet. Im afraid
there may be not any laws. Then well wonder where science is going, what
science means because were always out there looking for the next big
equation and (unintelligible)
can take us some place but it doesnt have any impact in nanoscience.
Right? There may be things that we discover about dark energy that we
dont know yet but, on the scale of nano science, we may just not have other
laws. We have lots of rules that we discovered, then you wonder where
were heading.
Sorry, theres another question.
Question: I have one question concerning the question of a fellow student
I know him.
Prof Strmer: I think you should use a microphone because I think nobody
can hear.
Audience: The new curricula of the new program of nanoscience was
initiated by our lecturer and I am in the team of people who initiated this
curricula and we are very happy that, in our university, we are not only
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studying chemistry and physics but biological department, biomedicine
department and across the street, we have a list including chemical
technology and includes many courses that are indexed in biology and
chemistry as a part of nanoscience. We would be happy to have good hands
in this background, good curricula.
Prof Strmer: I understand that the next year you will celebrate your 300th
anniversary. Im coming from Columbia where we just celebrated our 250th
anniversary two years ago. Youre always ahead of us! Its great, I mean
thats wonderful news.
Question: Can you explain..
Prof Strmer: Can you explain, in terms of the purity of the reaction? No,
Im afraid Im not enough of a chemist to do this. I know at some point Isaid 10 to the power of 23 molecules for ten dollars and theyre all identical.
Of course, theyre not and that is a big issue.
Chemists know that they do not have 100% success in their synthesis so
these are certainly things that somebody has to tackle but I would not be able
to give you an answer. This seems to be much more a chemists issue than it
is a physicists.
Prof Strmer: Okay, Im sorry, I misunderstood, youre asking about the
health implication? Okay, sorry, youre bringing up an interesting point.
Sorry I misunderstood. I think that the point that youre bringing up is
whether on the nano scale, if we are creating objects on the nano scale, what
will be the impact on biology in general and, perhaps, health sciences and
health? Its a question that is being asked in the United States more and
more and I think its very good that its being asked, I mean one of the
concerns, for example, whether the nano tubes have similar kind of effects
as asbestos because when you inhale it and I think 10% of the budget on
nano science is now being spent on the health implications of nano science
and I think this is very important to do, no question about it. And we have tosafeguard ourselves that whatever we do in the nano sphere does not have
detrimental health effects so I think this is money wisely spent. It could be a
lot more expensive afterwards but, more so, we want to make sure that we
wont have a negative health impact. On the other hand, this should not
keep us from pushing on with nanaoscience because we are saying theres
some negative impact. We should be studying this in a scientific way and
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understand what the health impact is. Probably we will find things that we
have to be very careful with and others that are really benign. I think its the
right attitude to study the health impacts at the same time as we study the
science.
Prof Strmer: Youre talking about the nanobots? Youre concerned that
carbon nano tubes will take over the world? Well, what youre doing is
youre asking the question. I cannot give you the answer. I mean I feel, I
feel that we are in terms of self assembly, the one that is guiding these
rumors. We are so much at the beginning that questions about runaway self
assembly are so much in the future. I believe we do not have a problem to
be very much concerned about at the moment. I think at some point, if what
I showed you in growing laptops on trees would ever come to fruition, I
mean before that wed certainly have to start worrying about not having real
trees anymore, only laptops. So, yes, but I think that it is far in the futureand, of course, it was only a loose picture. I do not want to grow laptops on
trees. I want to self assemble soft units. You have a concern and youre not
the only one but I think this is something that is far in the future and will be
decided not by us but, at the end of the day, by our children and, perhaps, by
our childrens children. But all this world is about what we want to get out
if it and that is further down the line. The decision in this context will be
made by other generations but I think thats no concern of ours.
Speaker: Im afraid that I have to say