SUNMONTUEWEDTHUFRISAT
Conferences, Lectures, & Seminars
Events for April
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“Energy-Optimal Scheduling with Dynamic Channel Acquisition in Wireless Downlinks”
Tue, Apr 03, 2007 @ 03:30 PM - 04:30 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Mr. Chih-Ping Li, Communication Sciences InstituteAbstract: We consider a wireless base station serving L users through L time-varying channels. It is well known that opportunistic scheduling algorithms with full channel state information (CSI) can stabilize the system and achieve the full capacity region of a wireless downlink. However, opportunistic scheduling algorithms with full CSI may not be energy efficient when the cost of channel acquisition is high and traffic rates are low. In particular, under the low traffic rate regime, it may be sufficient and more energy-efficient to transmit data with no CSI, i.e., to transmit data blindly, since no power for channel acquisition is consumed. However, pure channel-aware or pure channel-blind strategies are not necessarily optimal, and we must consider mixed strategies. We derive a unified scheduling algorithm that dynamically chooses to transmit data with full or no CSI based on queue backlog and channel statistics. Through Lyapunov analysis, we show that the unified algorithm can stabilize the downlink with optimal power consumption. Bio: Chih-ping Li received B.S. and M.S. degree in electrical engineering from National Taiwan University, Taiwan, in 2001 and University of Southern California in 2005, respectively. He is currently working toward the Ph.D. degree in USC. His research interests are in the areas of queueing theory and Markov decision processes.Host: Michael Neely, mjneely@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - -248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Thoughts on Mixing for EXIT Charts
Thu, Apr 05, 2007 @ 03:30 PM - 04:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Dr. Jossy Sayir, Telecommunications Research Center (FTW)ABSTRACT: EXIT charts and density evolution are two analysis techniques
to predict the peformance of iterative algorithms. EXIT charts
track the evolution of the average bitwise mutual information,
while density evolution tracks the evolution of the average
message distributions. In this talk, I will investigate the
difference between averaging mutual informations and averaging
distributions. A recent paper by Lechner, Kramer and Pedersen
shows that for messages that satisfy the symmetry condition
(e.g., Log-Likelihood Ratios), averaging distributions or
mutual informations are equivalent. For sub-optimal algorithms
(e.g., min-sum, Gallager A&B, etc.), where messages do not satisfy
the symmetry condition, they suggest a modification of EXIT chart
analysis that averages distributions in order to get the correct
prediction. We show that this does not necessarily yield the
correct prediction in all cases, and propose an alternative method
based on averaging mutual informations that does.This is joint work with Ingmar Land.BIO: Dr. Jossy Sayir received his Dipl. El.-Ing. degree from the ETH Zurich
in 1991. From 1991 to 1993, he worked as a development engineer for
Motorola Communications in Tel Aviv, Israel, contributing to the
design of a digital mobile radio system. He returned to ETH from 1993
to 1999, getting his PhD in 1999 under the supervision of Prof. J.L. Massey.
His thesis "On Coding by Probability Transformation" covered topics in
data compression, joint source-channel coding using arithmetic
codes, and capacity computation algorithms. Since 2000, he
has been employed at the Telecommunications Research Center (FTW) in
Vienna, Austria, as a senior researcher. His research interests
include iterative decoding methods, sub-optimal and quantized decoders,
and wireless ad hoc and sensor networks. Since July 2002, he manages
part of the strategic research activities at FTW and supervises a group
of researchers. He has taught courses on Turbo and related codes at
Vienna University of Technology, at the University of Aalborg,
Denmark, and at the University of Adelaide, Australia. He has served on
the organization committees of several international conferences and
workshops. In his spare time, he loves to cook, and plays the alto saxophone
in various jazz ensembles.HOST: Giuseppe Caire, caire@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - -248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
The Worlds Energy Problem and What We Can Do About It
Tue, Apr 10, 2007 @ 04:00 PM - 05:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Dr. Steven ChuDirector, Lawrence Berkeley National LaboratoryProfessor, University of California, BerkeleyNobel laureate, Physics, 1997AbstractAmong America's most serious concerns are (i) national security, which is intimately tied to energy security, (ii) economic competitiveness, and (iii) the environment. These issues transcend our national
boundaries and have serious implications for the world. At the core of these problems is need to secure, clean, affordable and sustainable sources of energy. Solutions must come from a combination
of improvements on both the demand and supply side, and science and technology will be an essential part of the solution. After briefly describing the energy problem, the remainder of the talk will describe areas of research that may lead to transforming technologies.BioSteven Chu is Director of the Lawrence Berkeley National Laboratory, Professor of Physics, Molecular
and Cellular Biology, University of California, Berkeley. Previously, he was at Stanford and Bell Laboratories. His research includes tests of fundamental physics, the development of methods to laser cool and trap atoms, polymer physics, and single molecule biology. He is become active in the energy problem and is co-chairing an InterAcademy Council (IAC) study "Transitioning to Sustainable
Energy". Chu has numerous awards, including the 1997 Nobel Prize in Physics. He is a member of the National Academy of Sciences, the American Philosophical Society, the American Academy of Arts and Sciences, the Academia Sinica, and a foreign member of the Chinese Academy of Sciences and the Korean Academy of Science and Engineering. At Stanford, he helped start Bio-X, a multi-disciplinary initiative linking the physical and biological sciences with engineering and medicine. He serves on the Boards of the Hewlett Foundation, the University of Rochester, NVIDIA and the Scientific Board of the Moore Foundation. He has served on a number of other committees such as the Augustine Committee that produced the report "Rising Above the Gathering Storm", the Advisory
Committee to the Directors of the NIH and the National Nuclear Security Agency, the Executive
Committee of the NAS Board on Physics and Astronomy. Professor Chu received A.B. and B.S. degrees in mathematics and physics from the University of Rochester, a Ph.D. in physics from UC Berkeley, and eight honorary degreesLocation: Ethel Percy Andrus Gerontology Center (GER) - 124 (Auditorium)
Audiences: Everyone Is Invited
Contact: Ericka Lieberknecht
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Floppy Forensics: Why you need a Ph.D from USC 20 years later
Fri, Apr 13, 2007 @ 12:30 PM - 01:15 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Dr. Fred Cohen: On June 21, 2005, I received the one and only floppy disk purported to have been originally written in the 1980s that was the key piece of evidence in a legal matter worth at least tens of millions of dollars. The reason I got it was that nobody else could read it. This talk is about how I extracted the contents, how sure I am that what I extracted is what was originally written some 20 years earlier and not a forgery created to win millions of dollars in a legal battle, and why I am that sure. It involves a hundred floppy disk drives, aging computers and long ago software libraries, flux density, electromechanical systems, a custom version of an operating system, a spiral disk, a trip to a military base in the desert that I made when I was a graduate student, coding and finite state machines, a trip to Alaska, and more. It is the proof that 20 years later, the things you learn on the way to getting your Ph.D. are still useful.
Location: Grace Ford Salvatori Hall Of Letters, Arts & Sciences (GFS) - 106
Audiences: Everyone Is Invited
Contact: Annie Yu
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Cognition, Computers, and Managing Perception - Dr. Fred Cohen
Fri, Apr 13, 2007 @ 02:00 PM - 03:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
People who break into computers lie all the time in their attacks, but what happens to the attackers when the computers lie back to them? In this talk, Dr. Cohen will describe what is believed to be the largest and most complete scientific experiments ever undertaken to test out an information security approach, the methodologies developed to carry out these experiments, the laboratory facilities used to support these experiments, and of course the underlying theory, experiments, and outcomes. Along the way, magic tricks will be used to demonstrate and clarify the theoretical underpinnings of the use of deception for information protection.
Location: Seeley G. Mudd Building (SGM) - 101
Audiences: Everyone Is Invited
Contact: Annie Yu
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Quantized Feedback Design for MIMO Broadcast Channels
Fri, Apr 13, 2007 @ 03:00 PM - 04:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Professor Mikael Skoglund, KTH, SwedenABSTRACT: Low-rate feedback design for multiple-input multiple-output broadcast channels is studied under a vector quantization framework. Iterative algorithms are proposed to design the partial feedback link, the scheduler, and the linear precoding codebook. It is demonstrated that the gain due to multi-user diversity can be significant even with heavily quantized channel state information at the transmitter. Our results highlight the potential of multi-user diversity, even with simple schemes and extremely-low-rate feedback.BIO: Mikael Skoglund received the Ph.D. degree in 1997 from Chalmers University of Technology, Gothenburg, Sweden. In the same year he joined the Royal Institute of Technology (KTH), Stockholm, Sweden. Here he held various positions until he was appointed Professor of Communication Theory in 2003.Dr. Skoglund's research interests are in information theory, communications, and detection and estimation. He has worked on problems in vector quantization, combined source-channel coding, coding for wireless communications, and statistical signal processing. Dr. Skoglund has authored some 100 scientific papers. Several of these have received best paper awards, and one recent journal paper ranks as 'highly cited' according to the ISI Essential Science Indicators.Dr. Skoglund is frequently serving as area expert and reviewer for research grants and publications, and he is an Associate Editor with the IEEE Transactions on Communications. Dr. Skoglund has also consulted for industry, and he holds 6 patents. He is a senior member of the IEEE.Host: Giuseppe Caire, caire@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - -248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Quantum Algorithms and Quantum State Identification
Tue, Apr 17, 2007 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Andrew Childs
California Institute of TechnologyHost: Todd Brun, tbrun@usc.eduABSTRACT:
Quantum mechanical computers would be much faster than ordinary classical computers at solving certain problems, such as factoring integers. However, the full extent of the computational power of quantum mechanics is not well understood. In this talk, I will describe recently developed quantum algorithms that outperform classical computation. These algorithms are based on efficient procedures for identifying quantum states. A simple example of a problem that can be solved in this way is the abelian hidden subgroup problem (HSP), the core problem solved by the factoring algorithm. I will explain how entangled measurements can be used to extend this approach to certain nonabelian HSPs. I will also describe how a similar approach can be applied to a new generalization of the abelian HSP, namely a problem of finding hidden nonlinear structures.BIOGRAPHY:
I received a B.S. in physics in 2000 from Caltech, and a Ph.D. in physics in 2004 from MIT, where I was a Hertz Foundation Fellow. Currently, I am a Lee A. DuBridge Postdoctoral Scholar at the Caltech Institute for Quantum Information. My primary research interest is the theory of quantum information processing, and I am especially interested in quantum algorithms that dramatically outperform classical computation.Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Alma Hernandez
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Game Theoretic Analysis of Wireless MAC
Tue, Apr 17, 2007 @ 02:30 PM - 03:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Abstract:
Many wireless network standards include Quality-of-Service (QoS) features at the MAC layer. These features provide nodes transmitting real-time traffic such as voice and video preferential access to the channel over nodes carrying best-effort traffic. The success of these QoS mechanisms requires that nodes be honest and truthfully report their application's QoS category. However rational nodes will, if they can, deviate from a standard's specification to maximize their utility. Network interfaces are becoming increasingly programmable and it is possible for nodes to falsely classify their best-effort traffic as real-time traffic to obtain increased throughput. In this talk, we will provide a game-theoretic analysis for a slotted Aloha like MAC that resembles the IEEE 802.11e MAC in many essential respects. Our MAC model allows traffic to be classified as either high-priority (HP) or low-priority (LP), and allows for both random access (contention) and polled (contention-free) channel access. We advocate the use of the contention-free access feature as an efficient and protocol-compliant mechanism to incentivize LP users to be truthful. We discuss appropriate utility functions for HP and LP traffic and analyze the performance of the system using the Nash bargaining solution (NBS) concept from cooperative game theory. The NBS concept is used to find a fair and Pareto-optimal operating point for our system. Since users are strategic, we then use the framework of non-cooperative game theory to find the set of Nash equilibria. Somewhat remarkably, we find that the NBS operating point is a Nash equilibrium, implying that our strategy is both efficient and strategy-proof.
Bio:
Pavan Nuggehalli received the M.Sc (Engg.) degree in electrical sciences from the Indian Institute of Science, Bangalore, in 1998 and the Ph.D. degree in electrical and computer engineering from the University of California at San Diego, La Jolla, in 2003. His research focuses on architectures, protocols and performance analysis of wireless ad hoc and sensor networks.
He is an Assistant Professor in the Centre for Electronics Design and Technology, Indian Institute of Science, Bangalore, and currently visiting the California Institute for Telecommunications and Information Technology (Calit2) at UC San DiegoHost: Prof. Bhaskar Krishnamachari, Ext. 12528 http://engineering.usc.edu/calendar/Location: Frank R. Seaver Science Center (SSC) - 319
Audiences: Everyone Is Invited
Contact: Shane Goodoff
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
The transformation design method and metamaterials: tools to realize invisibility cloaks and other i
Wed, Apr 18, 2007 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
David SchurigMing Hsieh
Department of Electrical EngineeringSEMINAR
"The transformation design method and metamaterials: tools to realize invisibility cloaks and other interesting devices"Abstract:
I will explain how the transformation design method works. One begins this design process by imagining a fictitious space with an interesting or useful property, for example, a hole for hiding things, or a "dense" region that concentrates energy. I will explain how such fictitious spaces can be described mathematically by a coordinate transformation. Then I will explain how the theories of such coordinate transformations and the form invariance of Maxwell's equations leads directly to a material specification. This material specification can implement the electromagnetic properties of the interesting fictitious spaces in the boring, approximately "flat", three dimensional spaces in which we live.
We have used this method to design invisibility cloaks, but the method is quite general and can be used to design a wide variety of interesting devices that guide, concentrate or shape electromagnetic fields in ways that would be difficult to manage with other design methodologies. Applications range from stealth to energy conversion and distribution to wireless communications to biomedical imaging.
The drawback of the method is the complexity of the material specifications that it produces, which have particular anisotropy (variation with angle) and inhomogeneity (variation with position). Only with recent advances in the field of metamaterials can these specifications be realized. I will discuss how metamaterials accomplish this and what their limitations are, e.g. bandwidth, absorption, frequency range etc.
I will discuss in detail the recent implementation of an invisibility cloak in the microwave spectrum. Unlike, traditional stealth, an invisibility cloak reduces both reflection and shadow. Thus both these ways of detecting an object, (the reflection of electromagnetic waves incident on the front of an object and the blocking of electromagnetic waves originating from behind the object) are weakened. If such a cloak were implemented for visible light (a daunting task), then when one looked at the cloaked object one would see the scene behind it.Biography:
David Schurig received his BS in Engineering Physics from U.C. Berkeley, and then worked at Lawrence Berkeley Lab on laser ablation and photoacoustic spectroscopy. He attended physics graduate school at U.C. San Diego and received a PhD in 2002 for his thesis on negative index media, the perfect lens and related structures. David also worked for the California Space Institute, performing space mission feasibility studies, and for Tristan Technologies, designing and building, cryogenically cooled, SQUID-based instruments. David is now a post doctoral fellow at Duke University. He is designing invisibility cloaks and other interesting devices using the transformation method and implementing them with metamaterials.
Location: Hedco Neurosciences Building (HNB) - 100
Audiences: Everyone Is Invited
Contact: Ericka Lieberknecht
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
QoS Maps for Mobile Wireless Networks: Coherence Time versus Node Mobility
Thu, Apr 19, 2007 @ 01:00 PM - 02:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Prof. Volkan Rodoplu, Dpt. of Electrical and Computer Engineering, University of California Santa BarbaraABSTRACT: The wireless networks of the next 10 years will consist of a plethora of microprocessor-sensor units embedded in clothes, shoes, cars, buses, as well as the more traditional portable handhelds, and laptops. Today, information flows in wireless networks via a limited number of wireless gateways. In the future, information is expected to flow through thousands to millions of wireless devices themselves. Most of these devices will be mobile and energy-limited, and will have to make decisions on the fly on how to communicate information through thousands to millions of other devices in between to reach destination nodes, as well as gateways into the wired domain. It will no longer be possible to track individual paths and individual nodes; hence, it is essential that an aggregate view of the essential qualities of the mobile network be built and be made available. Quality-of-Service (QoS) decisions regarding energy consumption, delay, and throughput will still play a prominent role in making intelligent decisions to conserve the limited energy supply of devices, and meet delay and throughput requirements in these future networks that consist of thousands to millions of mobile, microprocessor-sensor devices.With this vision, in this talk, we develop new methodologies for mobile, large-scale wireless sensor networks. We propose a novel framework to share, retain and refine end-to-end QoS metrics in the joint memory of the nodes, over time scales over which this information can be spread to the network and utilized for energy planning decisions. In analogy with the point-to-point link concepts, we introduce the "coherence time" of end-to-end QoS metrics for mobile wireless networks. We show that as long as the coherence time of QoS metrics is much larger than the "spreading period", mobile wireless networks can track end-to-end QoS metrics. This is a surprising conclusion given our current understanding of mobile networks, which correlates tractability with the amount of individual node mobility rather than the coherence time of QoS metrics.As an example of this methodology, we construct "energy maps," which are maps of the end-to-end energy metrics in space. We show how to (1) compute the spatial derivatives of energy potentials in mobile networks, (2) construct energy maps on-demand via path integration methods, and (3) distribute, share, fuse, and refine energy maps over time by information exchange during encounters. In order to put the energy maps to use, we present an algorithm for energy optimization, based on the energy maps, that finds the optimal bit allocation strategy to minimize the energy consumption, subject to a delay constraint. We show that significant energy savings are obtained by leveraging network mobility and the energy maps, when compared with a competing algorithm that allocates the traffic at a constant rate without utilizing the energy map. These techniques show how future, large-scale, mobile wireless sensor networks can be handled via new techniques, and how to generalize physical layer concepts such as coherence time, to network-layer concepts related to QoS issues.
This is joint work with Min Kyoung Park (Ph.D. alumna, UCSB)BIO: Volkan Rodoplu received his B.S. degree in Electrical Engineering (summa cum laude) from Princeton University in 1996 and his M.S. degree in Electrical Engineering from Stanford University in 1998. He worked for Texas Instruments (Dallas, TX) in the summer of 1998, on multiuser detection and interference cancellation algorithms, and for Tensilica, Inc. (Santa Clara, CA) in 2000-2001, on turbo decoding algorithms and architectures for reconfigurable processors. He received his Ph.D. in Electrical Engineering from Stanford University in 2003, and subsequently joined the Department of Electrical and ComputerEngineering at UCSB as an Assistant Professor. His research investigates the limits of minimum energy networks as well as the delivery of minimum energy networking solutions. His research areas span underwater networks, terrestrial wireless mobile sensor networks, and applications of cooperative game theory to wireless networks. He is the recipient of the NSF CAREER Award (2007), UC Regents' Junior Faculty Fellowship (2006), Department of Electrical Engineering Outstanding Service Award at Stanford (2000), B.George B. Wood Legacy Prize, and G. David Forney Prize (1996), and the John W. Tukey Award (1995).Host: Bhaskar Krishnamachari, bkrishna@usc.eduLocation: Frank R. Seaver Science Center (SSC) - 319
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Photophysics of Carbon Nanotubes
Wed, Apr 25, 2007 @ 11:00 AM - 12:00 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Dr. Mildred DresselhausInstitute Professor,
Massachusetts Institute of TechnologyAbstractThe use of resonance Raman spectroscopy to reveal the remarkable optical properties of carbon nanotubes arising from their one-dimensionality will be briefly reviewed. Particular emphasis will be given to the difference in behavior between semiconducting and metallic nanotubes and the dependence of these behaviors on diameter and chirality. Some of the recent advances in single nanotube photophysics based on both resonance Raman spectroscopy and photoluminescence will be discussed. A brief summary will then be given of current photophysics research directions pursued
in my research group.BioMildred Dresselhaus is an Institute Professor of Electrical Engineering and Physics at MIT. She is a member of the National Academy of Sciences, the National Academy of Engineering, and has served as President of the American Physical Society, Treasurer of the National Academy of Sciences,
President of the American Association for the Advancement of Science (AAAS), and on numerous
advisory committees and councils. Dr. Dresselhaus has received numerous awards, including
the National Medal of Science and 22 honorary doctorates worldwide. She is the co-author of four books on carbon science and is particularly well known for her work on carbon nanotubes and other nanostructural systems. Her research over the years has covered a wide range of problems in Condensed Matter and Materials Physics. She is presently co-chair of a National Academy Decadel Study of Condensed Matter and Materials Physics and is coming out this year with two new books, one entitled "Applications of Group Theory to the Physics of Condensed Matter" and the second entitled "Carbon Nanotubes: New Topics in the Synthesis, Structure, Properties and Applications." In February she was named the North American Laureate for the 2007 L'Oreal-UNESCO Award for Women in Science.More Information visit: http://ee.usc.edu/munushianLocation: Hedco Neurosciences Building (HNB) - 100
Audiences: Everyone Is Invited
Contact: Ericka Lieberknecht
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Optical Forces and Slow Light in Nanophotonics
Mon, Apr 30, 2007 @ 03:30 PM - 04:30 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Dr. Michelle L. PovinelliStanford UniversityMonday, April 30, 2007SSC 150 @ 3:30 PM to 4:30 PMAdvances in nanofabrication techniques now allow us to pattern materials on a scale
smaller than the wavelength of light. I will show how computational simulations can be used to explore novel optical phenomena in nanofabricated devices such as photonic
crystals and guide device design. First, I explore the use of optical (or radiation-pressure)forces for reconfiguration and positioning of integrated optical devices. Calculations on waveguide, microsphere, and photonic-crystal systems show that light forces should lead to significant displacements, opening a new route for all-optical control. Second, I describe how dynamically-tuned photonic crystals can be used to slow down the speed of light onchip, mimicking atomic systems. Thirdly, I describe mechanisms for reducing the propagation losses due to disorder and light leakage in miniaturized nanophotonic waveguides.Dr. Michelle L. Povinelli is a postdoctoral researcher at Stanford University in the Ginzton Laboratory and the Department of Electrical Engineering. She received a PhD in Physics from MIT in 2004, an M. Phil. in Physics from the University of Cambridge in 1998, and a BA with Honors in Physics from the University of Chicago in 1997. She was awarded several graduate fellowships for her doctoral work, including the Lucent Technologies GRPW Fellowship, the NSF Graduate Fellowship, the MIT Karl Taylor Compton Fellowship, and the Churchill Fellowship. In 2006, she was selected as one of five national recipients of a $20,000 L'Oréal For Women in Science Postdoctoral Fellowship grant. She has co-authored twenty refereed journal articles and holds two US Patents.Location: Frank R. Seaver Science Center (SSC) - 150 @ 3:30 PM
Audiences: Everyone Is Invited
Contact: Ericka Lieberknecht
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor.
