“lighting the way to technology through innovation”
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“Lighting the Way to Technology through Innovation”. The Institute for Lasers, Photonics and Biophotonics University at Buffalo Emerging Opportunities In New Directions of Photonics: Nanophotonics and Biophotonics P.N.Prasad. www.biophotonics.buffalo.edu. NANOPHOTONICS. - PowerPoint PPT PresentationTRANSCRIPT
“Lighting the Way to Technology through Innovation”
The Institute for Lasers, Photonics and Biophotonics
University at Buffalo
Emerging Opportunities
In New Directions of Photonics:
Nanophotonics and Biophotonics
P.N.Prasadwww.biophotonics.buffalo.eduwww.biophotonics.buffalo.edu
Nanoscale Optical Interaction and Dynamics:
Nonradiative Processes for Photonic Functions/Dynamics <10 nm
Optically Induced Photonics Functions/Dynamics sub wavelengths
Manifestations:
Size Dependent Optical Transitions
Novel Optical Resonances
Nano-control of Excitations Dynamics
Manipulation of Light Propagation
Nanoscopic Field Enhancement
NANOPHOTONICS
NANOPHOTONICS Paras N. Prasad
(John Wiley & Sons, April 2004)
SUMMARY OF CONTENTS
1. Introduction 2. Foundations for Nanophotonics 3. Near Field Interaction and Microscopy 4. Quantum Confined Materials 5. Plasmonics 6. Nanocontrol of Excitation Dynamics 7. Processing and Characterization of Nanomaterials 8. Nanostructured Molecular Architectures 9. Nanocomposites 10. Photonic Crystals 11. Nanolithography 12. Biomaterials for Nanophotonics 13. Nanophotonics for Biotechnology and Nanomedicine 14. The Market Place for Nanophotonics
Nanocomposites for Broad Band andEfficient Photovoltaic, Solar Cells
Hole transporting polymer + Inorganic semiconductorquantum dots
Features:
• In corporation of quantum dots to produce a direct junction between the polymer and the quantum dots.
• Efficient photosensitization over a broad wavelength covering from UV to IR by choice of the size and type of inorganic
semiconductor nanocrystals ... efficient solar harvesting.
• Enhanced carrier mobility for improved collection efficiency.
Quantum Engineering of InP/II-VI Core-shell nanocrystals
Etched InP nanocrystals and Core-Shell nanocrystals (302nm excitation)
InP, and InP/II-VI-Core-Shell Nanocrystals
Core/Shell nanocrystal
InP
II-VI
Core/Buffer/Shell nanocrystal(also magnetic nanocrystals)
InP
II-VI
II-VI
InP/CdS InP/CdSe Etched InP InP/ZnS
600 800 1000 1200 1400 1600 1800 2000 2200
0.0
0.5
1.0
1.5
2.0
Ab
sorb
an
ce [a
.u.]
Wavelength [nm]
0 10 20 30 40 50
0.0
1.0x10-2
2.0x10-2
3.0x10-2
4.0x10-2
Pho
toge
ner
atio
n Q
E,
[%]
Applied Field, E0 [V/m]
Size Tuning of Photosensitization in IR using PbSe Quantum Dots
(Dispersion in tetrachloroethylene)
Photogeneration Quantum Efficiency of PbSe Quantum Dots: PVK nanocomposites at 1.55µm
Transport of holes under the influence of external electric field
Photogeneration of charge carriers
Trapping of Space charge
Electro-optic Index modulation
z
+++ +++ +++- - -- - - - - -
+++ +++ +++- - - - - -- - -
- - -+++
- - -
+++
G
z
z
z
E
Multifunctionality in Photorefractivity:Multifunctionality in Photorefractivity: Photoconductivity + Electro-Optic Effect
~ 200 nm Liquid Crystal Nanodroplets
np no
ne ~ 10 nm Quantum Dots
PMMA:ECZ:LiquidCrystal:CdS
Photorefractive nanocomposite containing polymer-dispersed Liquid Crystal and Quantum Dots
Photorefractive inorganic-organic polymer-dispersed liquid crystal nano-composite photosensitized with
cadmium sulfide quantum dots
0 20 40 60 80 100
0
10
20
30
40
50
60
70
80
Diff
ract
ion
Eff
icie
ncy
, [%
]
Electric Field, E [V/m]
PMMA:TL202:ECZ:CdS 42:40:16:2 wt.%.
Q-CdS diam. < 1.4 nm = 514.5 nm
Winiarz and Prasad J., Opt. Lett. (in press)
Unaberrated Aberrated Corrected
Demonstration of the ability of the PMMA:ECZ:TL202:Q-CdS composite to correct a severely aberrated image under static conditions.
Photorefractivity for Correction of Beam Distortion
-3 -2 -1 0 1 2 30.00
0.04
0.08
0.12
0.16
0.20
0.24
0.28
0.32
0.36
band 2
band 1
Photonic Band Gap
Fre
quen
cy
Wavevector
Simple band picture for a photonic crystal
440 460 480 500 520 540 560 580 6000
20
40
60
80
100
Tra
nsm
ittan
ce [%
]
Wavelength [nm]
Transmission and reflection spectra
450 500 550 600 650 700 7500
20
40
60
80
100
Ref
lect
ance
[%]
Wavelength [nm]
3D colloidal crystal
Photonic crystals – A novel periodic photonic structure
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
X U L X W K
No
rma
lize
d f
req
ue
ncy
Wavevector [/a]
0.1 0.2 0.3 0.4 0.5 0.6 0.7
1.42
1.44
1.46
1.48
1.50
520nm1560nmE
ffective
refr
active
index
Normalized frequency
Novel Manifestations in Photonic Crystals
Complex band structure
Field enhancement- Low threshold lasing- Enhanced nonlinear optical effects
Superprism effect- Negative refraction- Large angle deflection- Ultradiffraction
Anomalous refractive index dispersion- Control of light propogation- Phase-matching for harmonic generation- Self-collimation
Third-Harmonic Generation in Photonic Crystals
2GW/cm 500I
40 nm off
Third-Harmonic Generation in Photonic Crystals
400 450 500 550 6000
500
1000
1500
2000
2500
Tra
nsm
ittan
ce
TH
G I
nten
sity
[a.
u.]
Wavelength[nm]
0.0
0.2
0.4
0.6
0.8
1.0
Third-harmonic generation in two polystyrene PCs (d=200 & 230 nm).
P. Markowicz at. al., Phys. Rev. Lett. - in press.
The intensity of THG from the 1-D photonic crystal as a function of the pump wavelength.
Advantages: Large Scale Area, Various Geometries, Simple, and One Step Processing
150 nm
Use of holographic (laser) photopolymerization to induce movement and sequester nanoparticles into defined 3-dimensional patterns
Holographic Illumination Intensity interference pattern
Sub-micron periods (50-800 nm)
Functional nanoparticles in reactive mixture
Spatially defined chemical reactivity
Light Driven Nanoparticle Alignment
Electrically Switchable Photonic Crystal
480 500 520 540 560 580 600
0.0
0.2
0.4
0.6
0.8
1.0
U=160V
U=0V
TH
Inte
nsity
[a. u
.]
Wavelength[nm]
480 500 520 540 560 580 600
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Transmission
THG
Inte
nsity
[a. u
.]Wavelength[nm]
Holographic polymer-dispersed liquid crystal grating.
The intensity of THG from the 1-D photonic crystal as a function of the applied voltage.
The transmission spectrum of the crystal & the third-harmonic signal.
In collaboration with AFRL, Dayton
Two-photon Lithography using femtosecond pulses
P. Crystal
Infiltration with Resin & 2-photon Lithography
P. Crystal & Linear Defects
Objective
1x2 Beam Splitter(5microns below surface)
Grating
Two-photon fluorescence
Photonic Crystal Defect Engineering: Optical Circuitry
One-photon fluorescence
In collaboration with Smalyukh and Lavrentovich, ILC, Kent State University
Laser Tweezers for micro- and nano- manipulation and surface adhesion
Multiple trapping in water by one beamLetters composed in Liquid Crystal
Measurement of colloidal forces and defect line tension and in liquid crystal
Introduction to Biophotonics Paras N. Prasad
(John Wiley & Sons, 2003)
SUMMARY OF CONTENTS 1. Introduction2. Fundamentals of Light and Matter3. Basics of Biology4. Fundamentals of Light-Matter Interactions5. Principles of Lasers, Current Laser Technology, and Nonlinear Optics6. Photobiology7. Bioimaging: Principles and Techniques8. Bioimaging: Applications9. Biosensors10. Microarray Technology for Genomics and Proteomics11. Flow Cytometry12. Light-Activated Therapy: Photodynamic Therapy13. Tissue Engineering with Light14. Laser Tweezers and Laser Scissors15. Nanotechnology for Biophotonics: Bionanophotonics16. Biomaterials for Photonics
Drug tracking using TPLSM
Doxorubicin : Chemotherapy drug
LHRH Peptide : Targeting agent.
C625 : Two-photon Chromophore
TPLSM images of MCF-7 cells showing the intake of drug into cell over a time period of 50 minutes.
= 800nmAvg. Power < 15mW=~ 90 fsf =82 MHz
Confocal images of MCF 7 cells. The arrows indicate The location where the spectra were taken.
Nucleus
Membrane
Cytoplasm
LHTPR
AC
Spectra profiles of AC&LHTPR treated MCF-7 cell (inside the Nucleus, Cytoplasm and on the Membrane)
Localized spectroscopy was used to identify the localization of a chemotherapeutic drug and and one of its component, the carrier protein, inside human cancer cells.
The ratio between the two emission at ~490nm (From AN152:C625) and the Emission at ~590 (From LHRH:TPR) was studied in different cell lines as well as in different parts of a cell to understand the roll of LHRH in carrying the drug into the cells.
Excitation Source: Ti:Sapphire laser tuned to a center wavelength of 800nm.
FGFR1-eGFP
Pre -Bleach Post -Bleach Recovery
0 100 200 300 400
0
10
20
30
40Nucleus
NM
PM
Time (s)
Flu
ore
sce
nc
e R
ec
ov
ery
(%
)
35.55 to 39.9771.70 to 82.0350.82 to
57.10
95% Confidence
37.6376.5253.78t½
(s)
Plasma MembraneNuclear MembraneNucleus
FRAP : A technique to monitor protien Dynamics in Cells