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Events for February 22, 2007
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Harnessing Vacuum Fluctuations: Exotic Physics and Micromechanics of the Casimir effect
Thu, Feb 22, 2007 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Federico CapassoHarvad UniversityAbstract
The Casimir effect is the attraction between uncharged metals in vacuum due to quantum mechanical fluctuations of the electromagnetic field (zero point energy). A similar force, but weaker, exists between dielectrics. From a physical point of view these forces are interesting because they represent macroscopic manifestations of quantum mechanics and because they can be designed by altering the shape and nature of the interacting materials. Interestingly these forces have enabled new functionalities in suitably scaled MEMS (nanometric position sensors) and will need to be accounted for in future generations of MEMS technology. The talk will also discuss on going experiments aiming at measuring repulsive Casimir forces, which could be used in frictionless bearings based on the phenomenon of "quantum floatation" and the search for the predicted "vacuum torque" between suitable birefringent materials.Bio
Federico Capasso received the doctor of Physics degree, summa cum laude, from the University of Rome, Italy, in 1973 and after doing research in fiber optics at Fondazione Bordoni in Rome, joined Bell Labs in 1976. In 1984 he was made a distinguished Member of Technical Staff and in 1997 a Bell Labs Fellow. In addition to his research activity Capasso has held several management positions at Bell Labs including Head of the Quantum Phenomena and Device Research Department and the Semiconductor Physics Research Department and Vice President of Physical Research. His current research in quantum electronics deals with the design of new light sources based on giant optical nonlinearities in quantum wells such as Raman injection lasers, inversioless injetcion lasers and widely tunable sources of TeraHertz radiation based on difference frequency generation and Raman lasers. He has also carried out research on quantum chaos in deformed microlasers which led he and his collaborators to invent microlasers opearting on bow-tie modes. More recently his research has expanded to high-precision measurements of Casimir forces using MEMS (MicroElectroMechanicalSystems)
and other quantum electrodynamical effects such as the torque between birefringent materials due to vacumm fluctuations. He is a Fellow of the American Physical Society, the Institute of Physics (UK), the Optical Society of America, the American Association for the Advancement of Science, IEEE and SPIE. He holds an honorary doctorate in Electronic Engineering form the University of Bologna, Italy. Capasso has co-authored over 300 papers, edited four volumes, and holds over 50 US patents.Website: ee.usc.edu/munushianLocation: Hedco Neurosciences Building (HNB) - 100
Audiences: Everyone Is Invited
Contact: Ericka Lieberknecht
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Optimal Computation with Noisy Quantum Walks
Thu, Feb 22, 2007 @ 02:00 PM - 03:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Dr. Viv Kendon, University of LeedsABSTRACT: Quantum versions of random walks on the line and cycle show a quadratic improvement in their spreading rate and mixing times respectively. The addition of decoherence to the quantum walk produces a more uniform distribution on the line, and even faster mixing on the cycle by removing the need for time-averaging to obtain a uniform distribution. By calculating the entanglement between the coin and the position of the quantum walker, the optimal decoherence rates are found to be such that all the entanglement is just removed by the time the final measurement is made. This requires only O(log T) random bits for a quantum walk of T steps.Bio: Viv Kendon works in the School of Physics and Astronomy at the University of Leeds, funded by a Royal Society University Research Fellowship, in the new Quantum Information group headed by Vlatko Vedral. Before this she was part of Peter Knight's Quantum Information and Quantum Optics Theory Group at Imperial College, and prior to Imperial (April 2000), was in the Computational Nonlinear & Quantum Optics group at Strathclyde University working on quantum measurement with Steven Barnett. Viv Kendon finished her PhD at Edinburgh in July 1999, in the Soft Condensed Matter group. Before her PhD, she used to work for GreenNet, a non-profit Internet service provider (now TWENTY years old!) and member the Association for Progressive Communications. She has also done work for Oxfam and Amnesty International. Prior to joining GreenNet she lived in Glasgow and was an active campaigner for Scottish Campagin for Nuclear Disarmament. Her first degree is from Oxford University, in Physics, and she has a Masters in Physics from UC Berkeley.Host: Todd Brun, tbrun@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
