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Proposed title: "Topological Phases and Applications to Quantum Information Processing" __________________________________________________________ List of organizers: Nicholas E. Bonesteel (Florida State University and NHMFL) Phone: (850) 644-7805, E-mail: [email protected] James P. Eisenstein (Caltech) Phone: (626) 395-4649, E-mail: [email protected] Michael H. Freedman (Microsoft Research) Phone: (805) 893-6313, E-mail: [email protected] Kirill Shtengel (UC Riverside) Phone: (951) 827-1058, E-mail: [email protected] Steven H. Simon (Lucent Technologies, Bell Labs) Phone: (908) 582-6006, E-mail: [email protected] __________________________________________________________ Proposed length: 4 weeks, preferably July 2 through July 29 or June 25 through July 22. However, anytime between June 18 and Sept 2, 2007 is acceptable. Pushing it toward earlier or later dates will result in conflicts with teaching for many of the potential attendees. __________________________________________________________ Abstract: Quantum computers, if realized in practice, promise exponential speed-up of some of the computational tasks that conventional classical algorithms are intrinsically incapable of handling efficiently. Perhaps even more intriguing possibility arises from being able to use quantum computers to simulate the behavior of other physical systems -- an exciting idea dating back to Feynman. Unfortunately, realizing a quantum computer in practice proves to be very difficult, chiefly due to the debilitating effects of decoherence plaguing all possible schemes which use microscopic degrees of freedom (such as nuclear or electronic spins) as basic building blocks. >From this perspective, topological quantum computing offers an attractive alternative by encoding quantum information in nonlocal topological degrees of freedom that are intrinsically protected from decoherence due to local noise. Over the last few years there have been substantial advances in both our understanding of how to compute with topological phases, and our understanding of topological phases themselves in various physical manifestations. The important features of these phases include topological order -- the ground state degeneracy that depends on the topology of the underlying 2D surface -- as well as nontrivial, often fractional statistics of their excitations. The goal of this workshop is to both study the physical nature of topological phases as well as to address the most important theoretical issues connected with any attempt to practically realize a topological quantum computer. One of the main objectives of the proposed workshop is to bring together experts from different fields including condensed matter physics, quantum optics and theory of quantum information and quantum computation. The exchange of ideas between researchers working on these subjects will hopefully result in making new inroads into this broad, inter-disciplinary field. Specifically, we hope to focus on the following topics. 1. Physical systems with topological order. So far, of experimentally observed systems, only Fractional Quantum Hall systems are believed to possess topological order. Numerous other possibilities have been discussed recently, ranging from atomic systems in optical lattices to Josephson junction arrays to frustrated magnetic systems. How to engineer systems supporting a topological phase remains an open question. 2. Fractional Quantum Hall Effect and related systems: Recently, new experiments purported to probe the quasiparticle statistics in the Fractional Quantum Hall systems have been reported by Goldman's group. However, their results appear to be open to interpretation. Hence a clear, unambiguous experimental evidence of fractional statistics remains to be confirmed. Experimental detection of non-Abelian anyons and related topological order remains an open problem despite several recent theoretical suggestions. How to control topological excitations, a crucial part of building a topological quantum computer, also remains to be explored. 3. Topological Algorithms and Computational Architectures: Given that such topological phases do exist, and are capable of performing universal quantum computation, one must ask how to build efficient architecture and how one would actually go about performing such computations. The structure of topological phases is extremely complex and imposing the traditional qubit architecture may not be the most efficient scheme. __________________________________________________________ List of potential attendees: Dorit Aharonov (Hebrew University, Israel) Ehud Altman (Weizmann Institute, Israel) Eddy Ardonne (Caltech and Microsoft Research) Dmitri Averin (SUNY Stony Brook) F.A. Bais (University of Amsterdam, The Netherlands) Leon Balents (UCSB) Cristina Bena (Rutgers) Gianni Blatter (ETH, Zurich, Switzerland) Sergey Bravyi (IBM) Hans Briegel (University of Innsbruck, Austria) Guido Burkard (University of Basel, Switzerland) Claudio Chamon (Boston University) Ignacio Cirac (Max Planck Institut, Garching, Germany) Nigel Cooper (Cambridge University, UK) Sankar Das Sarma (University of Maryland) Eugine Demler (Harvard) Rafi Di Picciotto (Lucent Technologies, Bell Labs) David DiVincenzo (IBM) Benoit Doucot (LPTHE-Jussieu, France) Marie Ericsson (Cambridge, UK) M. V. Feigelman (Landau Institute, Russia) Paul Fendley (University of Virginia) Matthew Fisher (UCSB) Eduardo Fradkin (University of Illinois, Urbana-Champaign) Dima Geshkenbein (ETH, Zurich, Switzerland) Vladimir Goldman (SUNY Stony Brook) Victor Gurarie (University of Colorado, Boulder) Duncan Haldane (Princeton) Bertrand Halperin (Harvard) Matthew Hastings (LANL) Moti Heiblum (Weizmann Institute, Israel) Michael Hermele (MIT) Dmitri Ivanov (EPF Lausanne, Switzerland) Lev Ioffe (Rutgers University) Jainendra Jain (Penn State) Woowon Kang (University of Chicago) Louis Kauffman (University of Illinois at Chicago) Eun-Ah Kim (Stanford)) Alexei Kitaev (Caltech and Microsoft Research) Michael Levin (Harvard) Claire Lhuillier (LPTL-Jussieu, France) Daniel Loss (University of Basel, Switzerland) Michael Manfra (Lucent Technologies, Bell Labs) Charles Marcus (Harvard) Gregoire Misguich (CEA-Saclay, France) Carlos Mochon (Perimeter Institute, Canada) Roderich Moessner (ENS-Paris, France) Joel Moore (UC Berkeley) Olexei Motrunich (Caltech) Chetan Nayak (UCLA and Microsoft Research) Michael Nielsen (University of Queensland, Australia) Gerardo Ortiz (LANL) Masaki Oshikawa (Tokyo Institute of Technology, Japan) Arun Paramekanti (University of Toronto) Vincent Pasquier (CEA-Saclay, France) Loren Pfeiffer (Lucent Technologies, Bell Labs) John Preskill (Caltech) Robert Raussendorf (Perimeter Institute, Canada) Nicholas Read (Yale) Gil Refael (Caltech) Edward Rezayi (CSLA) Subir Sachdev (Harvard) Anders Sandvik (Boston University) Vito Scarola (University of Maryland) Kareljan Schoutens (University of Amsterdam, The Netherlands) Didina Serban-Teodorescu (CEA-Saclay, France) T. Senthil (MIT) Joost Slingerland (Microsoft Research) Shivaji Sondhi (Princeton) Ady Stern (Weizmann Institute, Israel) Simon Trebst (Microsoft Research) Matthias Troyer (ETH, Zurich, Switzerland) Frank Verstraete (Caltech) Guifre Vidal (University of Queensland, Australia) Smitha Vishveshwara (University of Illinois, Urbana-Champaign) Ashvin Vishwanath (UC Berkeley) Zhenghan Wang (Microsoft Research) Kevin Walker (Microsoft Research) Paul Wiegmann (University of Chicago) Bob Willett (Lucent Technologies, Bell Labs) Xiao-Gang Wen (MIT) Amir Yacoby (Weizmann Institute, Israel) Peter Zoller (Innsbruck University, Austria) * where known, the future affiliations have been used. We have personally contacted a number of people on this list and have received supportive and enthusiastic responses. __________________________________________________________ A contact person: Kirill Shtengel <[email protected]> An organizer responsible for working to ensure diversity: Nicholas E. Bonesteel <[email protected]>.
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