************************************ * QUANTUM OPTICS AND ATOM OPTICS * * IN AUSTRALASIA * * * * * * * * MONTHLY NEWSLETTER * * VOL XI, NO 6 * * * CONTENTS: * June 2003 * * * 0. EDITORIAL NOTE * ISSN 1325-6467 * Edited by: 1. ABSTRACTS * * Alexei Gilchrist 2. VACANCIES * \ | / * Physics, University of Queensland, 3. BUY/SELL * \__|__/ * QLD 4072, Australia. 4. MISC NEWS * | * email: alexei@physics.uq.edu.au 5. CONFERENCES * | * phone: +61 7 3365 2422 * | * fax: +61 7 3365 1242 Available on WWW at: * * http://www.physics.uq.edu.au/qonews =============================================================================== 0. EDITORIAL NOTE =============================================================================== The Quantum Information conference in Singapore has been rescheduled from July till December 15-19 due to the problems with SARS. Cheers, Alexei =============================================================================== 1. ABSTRACTS =============================================================================== Proposal for a simple quantum error correction test gate in linear optics T.C.Ralph quant-ph/0306190 We describe a linear quantum optical circuit capable of demonstrating a simple quantum error correction code in a four photon experiment. ---------------------------------------------------------------------- Modal Dynamics for Non-Orthogonal Decompositions Jay Gambetta, H. M. Wiseman quant-ph/0306145 The modal interpretation of quantum mechanics allows one to keep the standard classical definition of realism intact. That is, things have a definite status for all time and a measurement only tells us which value it had. However, at present modal dynamics are only applicable to situations that are describe in the orthodox theory by projective measures. In this paper we extend modal dynamics to include positive operator measures (POMs). That is, for example, rather than using a complete set of orthogonal projectors, we can use an overcomplete set of nonorthogonal projectors. We derive the conditions under which Bell's stochastic modal dynamics for projectors reduce to deterministic dynamics, showing (incidentally) that Brown and Hiley's generalization of Bohmian mechanics [quant-ph/0005026, (2000)] cannot be thus derived. We then show how {\em deterministic} dynamics for positive operators can also be derived under some conditions. As a simple case, we consider a Harmonic oscillator, and the overcomplete set of coherent state projectors (i.e. the Husimi POM). We show that the modal dynamics for this POM correspond to the classical dynamics, even for the nonclassical number state $\ket{n}$, in the large $n$ limit. This is in contrast to the Bohmian dynamics (for the position projectors), which vanishes for energy eigenstates. ---------------------------------------------------------------------- Experimental requirements for Grover's algorithm in optical quantum computation Jennifer L. Dodd, Timothy C. Ralph, G. J. Milburn quant-ph/0306081 The field of linear optical quantum computation (LOQC) will soon need a repertoire of experimental milestones. We make progress in this direction by describing several experiments based on Grover's algorithm. These experiments range from a relatively simple implementation using only a single non-scalable CNOT gate to the most complex, requiring two concatenated scalable CNOT gates, and thus form a useful set of early milestones for LOQC. We also give a complete description of basic LOQC using polarization-encoded qubits, making use of many simplifications to the original scheme of Knill, Laflamme, and Milburn. ---------------------------------------------------------------------- Photon number superselection and the entangled coherent state representation Barry C. Sanders, Stephen D. Bartlett, Terry Rudolph, Peter L. Knight quant-ph/0306076 We introduce the entangled coherent state representation, which provides a powerful new technique for efficiently and elegantly describing and analyzing quantum optics sources and detectors whilst respecting the photon number superselection rule that is satisfied by all known quantum optics experiments. We apply the entangled coherent state representation to elucidate and resolve the longstanding puzzles of the coherence of a laser output field, interference between two number states, and dichotomous interpretations of quantum teleportation of coherent states. ---------------------------------------------------------------------- Quantum computation with optical coherent states T.C. Ralph, A. Gilchrist, G.J. Milburn, W.J. Munro, S. Glancy quant-ph/0306004 We show that quantum computation circuits using coherent states as the logical qubits can be constructed from simple linear networks, conditional photon measurements and "small" coherent superposition resource states. ---------------------------------------------------------------------- Photon Added Detection A. M. Branczyk, Tobias J. Osborne, Alexei Gilchrist, T. C. Ralph quant-ph/0305185 The production of conditional quantum states and quantum operations based on the result of measurement is now seen as a key tool in quantum information and metrology. We propose a new type of photon number detector. It functions non-deterministically, but when successful, it has high fidelity. The detector, which makes use of an n-photon auxiliary Fock state and high efficiency Homodyne detection, allows a tunable tradeoff between fidelity and probability. By sacrificing probability of operation, an excellent approximation to a photon number detector is achieved. ---------------------------------------------------------------------- Generating optical nonlinearity using trapped atoms Alexei Gilchrist, G. J. Milburn, W. J. Munro, Kae Nemoto quant-ph/0305167 We describe a scheme for producing an optical nonlinearity using an interaction with one or more ancilla two-level atomic systems. The nonlinearity, which can be implemented using high efficiency fluorescence shelving measurements, together with general linear transformations is sufficient for simulating arbitrary Hamiltonian evolution on a Fock state qudit. We give two examples of the application of this nonlinearity, one for the creation of nonlinear phase shifts on optical fields as required in single photon quantum computation schemes, and the other for the preparation of optical Schrodinger cat states. ---------------------------------------------------------------------- Comment on ``Testing integrability with a single bit of quantum information'' Howard M. Wiseman quant-ph/0305153 In quant-ph/0303042, Poulin, Laflamme, Milburn and Paz consider the problem of distinguishing quantum chaos from quantum integrability for dynamics in an $N$-dimensional Hilbert space. They claim that this can be done by deterministic quantum computing with a single bit using $O(\sqrt{N})$ physical resources, compared to O(N) physical resources classically. I point out what seems to be a fatal flaw with their proposal. =============================================================================== 2. VACANCIES =============================================================================== Postdoctoral Position in Quantum Optics and Quantum Information A postdoctoral Research Associate position in Quantum Optics and Quantum Information is available in the Physics Department of the University of Virginia, starting in the fall of 2003. The duration of the appointment is at least one year, renewable to up to three years. The successful applicant will be expected to conduct and analyze quantum optics experiments with ultra-stable OPO's. The goals are the investigation of continuous-variable quantum teleportation and quantum error correction, and the creation of non-Gaussian states of light. (See http://galileo.phys.virginia.edu/research/groups/qoqi/ for more information.) Submit a current CV and two letters of recommendation to Olivier Pfister at opfister@virginia.edu, or: Olivier Pfister, Department of Physics, University of Virginia, 382 McCormick Road, Charlottesville, VA 22904-4714, USA. The University of Virginia is an Equal Opportunity, Affirmative Action Employer. Women and minorities are strongly encouraged to apply. =============================================================================== 5. CONFERENCES / WORKSHOPS =============================================================================== ICOLS 03: 16th International Conference on Laser Spectroscopy 13-18 July 2003 Preregistration: 13 December 2002 Earlybird registration and abstracts: 28 April 2003 Palm Cove, AUSTRALIA http://www.swin.edu.au/rescentres/soll/icols03/icols.html Following the tradition of ICOLS conferences, the program will consist of single sessions of invited talks and posters covering the latest developments in Laser Spectroscopy and related topics. Scheduling will allow significant time for informal discussions. The number of participants will be limited to about 250-300. ------------------------------------------------------------------- ICOLS03 Satellite Meeting: Atomic Frequency Standards 21 July 2003 Registration Deadline: 1 July 2003 Sydney, Australia. A one-day Workshop on the Latest Developemnts in Atomic Frequency Standards will be held as a satellite meeting to ICOLS03 on 21 July 2003 at the CSIRO National Measurement Laboratory, Sydney. Invited speakers include: Professor Dr T. W. Hänsch, Max-Planck-Institut für Quantenoptik Dr Leo Hollberg, National Institute for Standards and Technology, Boulder A/Prof Michael Tobar, University of Western Australia Dr Hugh Klein, National Physical Laboratory, London An interim program for the meeting can be found at: ftp://time1.tip.csiro.au/pub/timedata/Interim_Program.doc Information on travel, accommodation and other issues can be found at: ftp://time1.tip.csiro.au/pub/timedata/Information.doc The registration fee is $A110, which includes lunch and dinner. Deadline for registration to enable dinner reservations to be secured: 1 July 2003 For further information, please contact Peter Fisk, peter.fisk@csiro.au, +61 2 9413 7221 ------------------------------------------------------------------- 4th European QIPC Workshop 13th - 17th July 2003 Submission deadline: 04 April 2003 Oxford, UK http://www.quiprocone.org/Oxford/4th_Keble.htm The purpose of the workshop is to promote interaction across the broad subject area of QIPC and follows previous meetings in Potsdam, ISI Torino and Trinity College Dublin. ------------------------------------------------------------------- 48th SPIE Meeting: Quantum Communications and Quantum Imaging (AM112) 3-8 August 2003 Abstract Due: 6 January 2003 Manuscript Due: 7 July 2003 http://spie.org/Conferences/Calls/03/am/conferences/index.cfm?fuseaction=AM112 Quantum communications and quantum imaging are emerging technologies that promise great benefits as well as great challenges. The objective of this conference is to provide a forum for researchers and system developers in both fields and encourage technology exchange between the quantum communication and quantum imaging communities. ------------------------------------------------------------------- IWQDQC: The 2nd International Workshop on Quantum Dots for Quantum Computing 7-9 August, 2003 Deadline for abstracts: 15 March 2003 Early registration: 1 July, 2003 University of Notre Dame, Indiana, USA http://www.nd.edu/%7Eiwqdqc/index.html The workshop is intended to be an international forum for discussions on the current trends and future directions of research in quantum dots and solid-state implementations for quantum computing. ------------------------------------------------------------------- QIT-EQIS: A Satellite Workshop to EQIS '03 2-3 Sept, 2003 Contributions: 15th July 2003 Kyoto, Japan http://www.qci.jst.go.jp/eqis03/qit-eqis/ The satellite workshop focuses on the theory of quantum communication, distinguishability and entanglement, including topics such as o channel capacities and resource tradeoffs o quantum source coding and data compression o quantum channel coding and error-correcting codes o state and channel distinguishability and tomography o entanglement and entanglement measures o additivity/nonadditivity results o quantum cryptographic theory o teleportation and entanglement-assisted communication o interaction as a communication primitive ------------------------------------------------------------------- EQUIS03: ERATO Conference on Quantum Information Science 3rd - 6th September 2003 Submission Deadline: July 15, 2003 Early Registration Deadline: August 9, 2003 Kyoto, Japan http://www.qci.jst.go.jp/eqis03/ The EQIS meetings are to focus on quantum information science and technology, a new interdisciplinary field bridging computer science, quantum physics, mathematics, optics- and nano-technologies. EQIS'03 will be the thrid conference in a series and is to concentrate on theoretical and also experimental aspects of quantum information science. ------------------------------------------------------------------- NQSI - Satellite Workshop to EQIS'03 Non-locality of Quantum Mechanics and Statistical Inference 8-9 September, 2003 Submission Deadline: July 25, 2003 Kyoto, Japan http://www.kyoto-su.ac.jp/conference/qm-kyoto/nqsi.html The development of Quantum Information Science, which is based on the central principles of quantum mechanics, forces us to confront once more the question: Do we really understand the quantum mechanics that we use for all practical purposes? Taking advantage of the international conference EQIS'03 where people working on quantum information science from several different fields will be gathered together, we have organized a satellite workshop on basic problems on quantum mechanics to discuss the points which need further clarification. ------------------------------------------------------------------- Quantum Optics - EuroConference on Cavity QED and Quantum Fluctuations: From Fundamental Concepts to Nano-Technology 27 September - 02 October 2003 Applications by 26 May 2003 Granada, Spain http://www.esf.org/euresco/03/pc03005 Quantum Optics is a very active and fast evolving field in physics with at its core the understanding and control of quantum systems. The objective of the Quantum Optics Euroconferences is to bring together the leading groups in the field with the emphasis on combining knowledge and technology of different subfields and identifying new promising directions. The 2003 Quantum Optics conference will focus on cavity quantum electrodynamics and quantum fluctuations, covering a broad range of topics from fundamental concepts of quantum optics to technological developments. Sessions will be devoted to cavity QED, Casimir forces and their impact in nanostructures, quantum information and decoherence phenomena, coherent atomic sources and BEC in atom chips and wave guides. In close connection with these topics a session will address the new emerging field of nano-optics. ------------------------------------------------------------------- 304th Heraeus-Seminar "Elementary Quantum Processors" 13th - 15th October 2003 Registration: August 31, 2003 Bad Honnef, Germany http://www.weh304.de/ Concepts for the implementation of elementary quantum processors abound in many areas of physics, including quantum optics, quantum dot physics, spin electronics, superconducting devices, and more. At the Physikzentrum leading researchers will survey the state of art in engineering elementary quantum logic devices. Intense scientific communication about this exciting topic is warranted. ------------------------------------------------------------------- Solid State Quantum Information Processing 15-18 December 2003 Registration: October 29, 2003 Amsterdam Renaissance Hotel, The Netherlands http://ssqip.tudelft.nl This conference aims at (1) reviewing the progress in quantum information processing using devices built in the solid state, (2) reporting the most recent results, and (3) identifying promises and challenges in this field. ------------------------------------------------------------------- 2nd Asia-Pacific Workshop on Quantum Information Science 15-19 December, 2003 Registration (+financial support request): September 30, 2003 Registration: October 19, 2003 Abstracts: October 31, 2003 Singapore http://www.physics.nus.edu.sg/%7Equantum/workshop/ Quantum Information Science is a fascinating interdisciplinary area that continues to capture the interest of physicists, mathematicians, chemists, engineers and computer scientists in recent years. In April 2001, we successfully organized a small scale international pedagogical workshop on the subject. Since then, there has been immense progress in this field. We have therefore decided to organise the Second Asia-Pacific Workshop on Quantum Information Science 2003 which will be held at the National University of Singapore from July 21, 2003 to 25 July, 2003. As in the previous workshop, the invited speakers will be delivering pedagogical talks on their areas of expertise and we will also be organising a special session for participants to share their findings through short oral presentations and poster exhibitions. Objectives: * To provide good pedagogical and introductory courses for researchers and graduate students who would like to learn about quantum information science * To promote exchanges of scientific knowledge in the field * To strengthen the ties among the scientists of the region who work in this area *** Addendum *** =============================================================================== 0. EDITORIAL NOTE =============================================================================== Some additional vacancies that have been brought to my attention... Alexei =============================================================================== 2. VACANCIES =============================================================================== Research associate (Joshu) Quantum information theory group Applications are invited for a research associate position (Joshu in Japanese) in the quantum information theory group. The main research interest of the group is to investigate new properties of entanglement and the use of these properties as resources for quantum information processing. The successful candidate must have, or be about to obtain, a Ph.D. in physics or a related field and share the group's research interests. The position will start as soon as an appointment is made. The research associate (Joshu) position is a national university teaching officer position and includes some teaching responsibilities (likely to be leading a weekly problem set session for half of the year), which can be given in English. The salary for the position will depend on the successful candidate's experience. It is expected that the research associate will vacate the position within 3-5 years of joining the group. We encourage both Japanese and international applicants. Japanese language proficiency is not a requirement. Applicants are required to submit 1. A curriculum vitae (including an email address) 2. A list of publications 3. A summary of research achievements (A4 one page) 4. A statement of research intentions (A4 one page) 5. Contact details (including email addresses) of two referees to Prof. Mio Murao, Department of Physics, Graduate School of Science, University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan by 1st September 2003. Informal enquires about this position may be made to Prof. Mio Murao (murao@phys.s.u-tokyo.ac.jp). ---------------------------------------------------------------------- Theoretical Physics , Research Fellow 1 Fixed-Term ( Three Years ) , Full Time , Nathan VRN SCN13627/03 Closing Date 08.08.03 Applications are invited for a Research Fellow in Quantum Measurement and Control Theory. The Fellow will work as part of the multi-institution Centre for Quantum Computer Technology, in the program "Quantum Measurement and Control for Quantum Information Processing". This includes theoretical studies of (i) realistic detection in solid-state and other quantum computer schemes, (ii) quantum feedback control, (iii) relations between quantum measurement and quantum information, (iv) synergies between quantum measurement and quantum computing. The successful candidate will have a PhD (Theoretical Physics), in the areas of quantum information processing, quantum optics, quantum measurement, or a related area. Key duties include contributing ideas, undertaking numerical and analytical calculations, and contributing to writing papers. The Fellow will have considerable freedom to pursue independent research. This is a full-time, fixed-term position (three years) . An appointment will be made at the level of Research Fellow Grade 1 or 2 based on the successful candidates qualifications and experience. Further information can be obtained from Dr Howard Wiseman, telephone: (07) 3875 7271, or email: h.wiseman@griffith.edu.au. Further information on the position can be obtained at http://www.gu.edu.au/jobs/scn1362703/home.htm.