NEWS for May 2009www.jqi.umd.edu

Joint Quantum Institute

Workshop:The Future of QI Science

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INSIDE

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Phase Changes and Transition Events

Image of theMonth: JQI GetsReady for DAMOP

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JQI Goes Public on 'Maryland Day'

Joint QuantumInstitute

Letterhead

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(1b)Joint Quantum InstituteNIST and the University of Maryland100 Bureau Dr.Gaithersburg, MD 20899

In recent weeks, it often seemed as if JQI were experiencing more shuffling than Saturday night in Reno, as various personnel prepared to arrive, depart or take on new positions.

Among the arrivals is new JQI Fellow Jacob (Jake) Taylor, coming to the National Institute of Standards and Technology (NIST) from MIT, where he has been a Pappalardo Fellow in Physics since 2006. Taylor, who got his PhD at Harvard under Mikhail Lukin, works on mesoscopic systems, quantum-information devices and interfaces between mesoscopic systems and quantum optics.

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By the end of a hot Saturday afternoon on April 25, some 77,500 visitors had made their way onto the University of Maryland's College Park campus for "Maryland Day" -- an annual event in which each department welcomes the public, conducts demonstrations and provides information. This year JQI had four continuous presentations: the ever-popular Meissner effect, a hands-on

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JQI Fellow Fred Wellstood explains a point to Maryland Day visitors.

Left: New JQI Fellow Jake Taylor, heading to NIST. Right: JQI Fellow Kris Helmerson, bound for Monash Univ. in Australia.

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Comings and Goings, from page 1

In describing his research interests, Taylor writes: "Mesoscopic devices such as semiconductor quantum dots and superconducting islands provide intriguing physical systems for implementing ideas from quantum information science. These devices can be engineered with specific, controllable, quantum mechanical behaviors, allowing them to be used to investigate the quantum properties of mesoscale systems.

"However, such systems are strongly coupled to their environment. One area of [my] research is in understanding this coupling and learning how to control quantum systems in the solid state. These problems present a major challenge for condensed-matter physics. Furthermore, integrating such quantum systems into a larger-scale device requires a systems-level approach to design. [I am] currently investigating the behavior of larger-scale networks of quantum bits with the aim of protecting complex quantum states from noise and errors."

On the departure side, JQI Fellow Kris Helmerson, of the Laser Cooling and Trapping group at NIST, has accepted a Professorship in the School of Physics at Monash University, which is in an eastern suburb of Melbourne. He will be setting up research programs in both atomic physics and biophotonics.

The atomic physics research will use ultracold atoms to study the role of topology and disorder on phenomena traditionally observed in condensed matter systems, such as superfluidity and quantum turbulence.

The biophotonics research will focus on development of techniques for studying non-equilibrium behavior of single biomolecules in highly confined geometries, similar to what goes on inside a cell.

"Ultracold atoms research in Australia has evolved significantly over the past several years," Helmerson says, and the university "is making a major commitment in this field, hiring young

faculty like Lincoln Turner (a former NIST post-doc at the Laser Cooling and Trapping Group), so it seemed like a particularly exciting time to start a research effort there. continued on next page

Bill Phillips on Kris Helmerson:

Kris influenced the field of coherent quantum matter in truly profound ways. As the leader of an experimental team investigating the nature and applications of Bose-Einstein condensates (BECs) he compiled an impressive list of "firsts" that have become landmarks for the field and standard practices in other labs around the world.

These include the first demonstrations of normal diffraction, Bragg diffraction and Bragg spectroscopy of a BEC, now standard tools of coherent atom optics; the application of these tools for atom interferometry with BECs, including its use in confirming the spatial coherence of a BEC; the demonstration of a new and powerful technique for making continuous atom lasers; the development of a vast body of work on the behavior of coherent atoms in optical lattices; the first demonstration of dynamical quantum tunneling of BECs; the first demonstrations of non-linear atom optical effects: four-wave-mixing and soliton propagation in BECs; the first demonstration of coherent rotation of a BEC using the orbital angular momentum of light; the first demonstration of a persistent flow in a toroidal BEC; and in work that has just appeared in Phys. Rev. Lett., new and exciting observations about the superfluid transition in a 2-dimensional Bose gas. In addition to his extensive work in atom optics and related areas, Kris has been a leader in the applications of optical tweezers to the study of biological and biochemical problems.

Kris's quiet good humor, his generosity to colleagues, students and staff alike, his vast storehouse of knowledge, as well as his scientific leadership, will be greatly missed.

Bill Phillips

Goings and Comings, continued from page 2

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"My experiences at NIST, and more recently at JQI, over the past 18 years have been exceptional. I've had the opportunity to work with first-rate people in a highly supportive environment on some extremely interesting science.

"I hope to recreate, as much as possible, a similar situation at Monash University and in the Australian ultracold atoms community in general. I am also hoping to maintain some link to the JQI, possibly through collaborative research or training of young researchers. Of course, I hope that all my colleagues and friends coming to Australia will stop by Melbourne and Monash, in particular. The next International Conference of Atomic Physics will be held in Australia in 2010."

Both JQI Co-Directors expressed regret at the departure. Steve Rolston, who came to the University of Maryland from NIST, noted that "I have known Kris since 1986, when we worked together in a group that

did the first trapping of antiprotons. In the two decades since, we have published many papers together. Kris and I built the sodium experiment that would eventually produce the first BEC experiments in Gaithersburg, and we would go on to work together on Bragg scattering, atom lasers, soliton formation, and four-wave mixing of matter waves, among other things.

"Kris has always been known for his quiet demeanor, which masks a biting sense of humor. It is always dangerous to sit next to him in a meeting because he will quietly mumble hilariously sarcastic comments that makes it difficult not to burst out laughing. We will miss him in the JQI for his physics, his humor, and his artistic talents, because he is a talented cartoonist as well. I wish him all the luck down under, and am sad to see him go. But I expect big things to come."

Carl Williams of NIST praised Helmerson as a "world-class scientist who has contributed tremendously to the field of atom optics, from the atom laser to the transfer of orbital angular momentum of light to a BEC. He will be missed as he moves on to the next stage of his research career both for his scientific leadership and his support of the broad NIST community."

Other JQI/NIST researchers are also off to academe:

Jay Vaishnav, a postdoc in JQI Fellow Charles Clark's group, has accepted an assistant professorship of physics at Bucknell University, and will move there in July or August.

Menderes Iskin, a guest researcher in JQI Fel-low Garnett Bryant's group who worked with Williams, has accepted an assistant professor position at the Department of Physics at Koc University in Istanbul, Turkey, and will move there in August.

Nathan Lundblad of JQI Fellow Bill Phillips' group will join the faculty of Bates College outside Portland, Maine this fall.

Xianli Zhang, a graduate student in Steve Rolston's ultracold plasma lab, defended his dissertation on April 6th, and will work as a postdoc in Mark Saffman's group at the University of Wisconsin at Madison. And Emily Edwards, another Rolston advisee who defended earlier this year, will

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Jay Vaishnav

Menderes Iskin

Steve Rolston

Carl Williams

Goings and Comings, continued from page 3

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be a postdoc in Rolston's ultracold matter group.

JQI will soon have two ad-ditional National Research Council Postdoctoral Research Associates.

One is Steve Olmschenk, of Chris Monroe's ion trap group, who defended on April 17th. (His thesis, "Quantum Telepor-tation Between Distant Matter Qubits," will be published in an upcoming issue of the Interna-tional Journal of Quantum Information.) He will join NIST's Laser Trapping and Cooling group this summer.

The other is Amy Cassidy, whose Ph.D. thesis on thermal-ization of quantum systems was supervised by Maxim Olshanii (Univ.of Massachu-setts). She will join Charles Clark's group in August.

Another Monroe group mem-ber, Peter Maunz, has been promoted to Assistant Re-

search Scientist by UMD Physics.

Finally, JQI has determined the fall 2009 roster of two Postdoctoral Fellows and four JQI Graduate Fellows. The postdocs are Stephen Powell and Ryan Barnett.

Powell, a Yale PhD, has been a postdoc at Oxford's Condensed Matter Theory Group. He will work on frustrated magnetism (including phase transitions in strongly constrained systems, and study of spin ices)

and ultracold atomic gases (including itinerant lattice magnets and quench dynamics).

Barnett, a Harvard PhD, was a postdoctoral fellow in theoretical physics at Caltech. He will concentrate on microscopic investiga-tions of competing orders in solid-state systems and in physics resulting from strong interactions in systems of ultracold atoms or molecules.

The four new JQI Graduate Fellows are: David Hucul (Michigan/MIT), Jeffrey Grover (Amherst), Crystal Senko (Duke) and Dvir Kafri (Rice). Steven Olmschenk

Nathan Lundblad

In January 2009, the United States National Science and Technology Council issued a report on A Federal Vision for Quantum Information Science. The report proposes that “The United States … create a scientific foundation for controlling, manipulating, and exploiting the behavior of quantum matter, and for identifying the physical, mathematical, and computational capabilities and limitations of quantum information processing systems in order to build a knowledge base for this 21st century technology.”

In response, the Workshop on Quantum Information Science met in Vienna, VA from April 23-25. JQI Co-Director Carl Williams gave the opening remarks, and JQI Fellow Bill Phillips gave a presentation on quantum computation and simulation with cold atoms. Both presentations, along with the rest of the workshop, are available at http://www.eas.caltech.edu/qis2009/index.

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Image of the Month: The World of JQI at DAMOP

JQI researchers will give 64 presentations at the May meeting of the American Physical Society's Division of Atomic, Molecular and Optical Physics (DAMOP). JQI Fellow Charles Clark produced the illustration above to highlight the range of coauthors: a total of 52 from 30 other institu-tions in 12 U.S. states and nine other nations. U.S. institutions providing the largest numbers are: Georgia Tech (9), Harvard ( 7), Georgia Southern Univ. (4), Univ. of Delaware (3), Louisiana State Univ. (2), Univ. of Michigan (2), Univ. of New Mexico (2), Yale (2) and UC-San Diego (2).

The numerous international collaborators hail from Universidad Autónoma de San Luis Potosií (Mexico), Australian National University and Monash University (Australia), Petersburg Nuclear Physics Institute (Russia), the Polish Academy of Sciences, Warsaw University and the University of Silesia (Poland), Tokyo University of Science (Japan), University of Innsbruck (Austria), University of Rennes (France), University of Ulm (Germany) and Wuhan Institute of Physics and Mathematics and South China Normal University (China).

JQI Meets the Public on "Maryland Day," from page 1

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display of various elemental spectra, a superconducting quantum interference device (SQUID) detecting magnetic fields, and numerous lab tours of experiments by the Steve Rolston and Chris Monroe groups.

Photos Above, left to right: JQI Fellow Steve Rolston walks through the crowd outside the UMD Physics building; graduate student Andrew Manning shows a visitor how to use the hand-held diffraction gratings to examine a spectrum from a gas arc tube; and JQI Fellow Chris Lobb talks about superconductors.

At left: Students prod a magnet levitating above a high-temperature superconductor. A close-up camera captured the action for projection onto a large screen.

Below: JQI Fellow Trey Porto discusses the Meissner effect for one of many audiences. Rolston and JQI Fellow Bob Anderson are seen at right.

Presentations

JQI Fellow Victor Yakovenko delivered the Ak-shoy K. Dutta endowment Professorship Lecture at the Indian Association for the Cultivation of Science in Kolkata, India, where C. V. Raman worked. The letter of invitation noted that "The distinguished stalwarts who visited and deliv-ered such lectures in the past include Professors Linus Pauling, Robert Burns Woodward, Sir Derek Barton, Roald Hoffmann, Ahmed Hassan Zewail, Gerard t’Hooft, David Gross, Björn Olof Roos, Henry Schaefer and many others." The title of Yakovenko's Mar. 13 presentation was "Theoreti-cal models of spontaneous time-reversal sym-metry breaking in Sr2RuO4 and in underdoped cuprates."

JQI Fellow Charles Clark will give a talk titled "Believe it or square root of NOT: quantum com-munication and quantum computing" at the Undergraduate Engineering Assembly, Johns Hopkins University on May 6.

In April, JQI Fellow Christopher Monroe pre-sented the Physics Colloquium and Quantum Information Seminar at the University of Illinois Urbana-Champaign. Monroe also gave two lec-tures at Walter Johnson High School in Bethesda, MD: "Quantum Bits and the Future of Informa-tion Processing" for the Computer Science class and "Quantum Mechanics without the Math" to the Advanced Physics Class.

Intelligence Community (IC) Postdoctoral Fellow Qudsia Quraishi presented her research at the annual IC Postdoctoral Research Fellowship Col-loquium in Chantilly, VA, April 27-30.

Publications

"Phase transitions, entanglement and quantum noise interferometry in cold atoms," F. Mintert, A. M. Rey, I. I. Satija and C. W. Clark, Europhysics Letters 86, 17003 (2009)

"Symmetry-breaking and symmetry-restoring dynamics of a mixture of Bose-Einstein conden-

sates in a double well," I. I. Satija, R. Balakrishnan, P. Naudus, J. Heward, M. Edwards, and C. W. Clark, Phys. Rev. A 79, 033616 (2009)

"Bose-Einstein Condensate in a Uniform Light-Induced Vector Potential," Y.-J. Lin, R.L. Compton, A.R. Perry, W.D. Phillips, J.V. Porto and I.B. Spiel-man, Phys. Rev. Letters 102, 130401 (2009)

"Quantum Phase Transitions and Continuous Ob-servation of Spinor Dynamics in an Antiferromag-netic Condensate," Y. Liu, S. Jung, S. E. Maxwell, L. D. Turner, E. Tiesinga, and P. D. Lett, Phys. Rev. Letters 102, 125301 (2009)

"Prediction of Feshbach resonances from three input parameters," Thomas M. Hanna, Eite Ties-inga, and Paul Julienne, Phys. Rev. A 79 040701(R) (2009)

Service

When the American Physical Society Council met last month, contained three JQI Fellows: Steve Rolston, Paul Julienne and Wendell Hill. They serve on the 30-person Council, the main gov-erning body of the APS.

Entangled States

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JQI is a joint venture of the University of Maryland and the National Institute of Standards and Technology, with support from the Laboratory for Physical Sciences.

Joint Quantum InstituteDepartment of Physics, Univ. of MarylandCollege Park, MD 20742E-mail: jqi_info@squid.umd.eduTelephone: (301) 405-6129