************************************ * QUANTUM OPTICS AND ATOM OPTICS * * IN AUSTRALASIA * * * * * * * * MONTHLY NEWSLETTER * * VOL VIII, NO 2 * * * * February 2000 * * * * ISSN 1325-6467 * * * Edited by: Bill Munro * \ | / * Physics, University of Queensland, * \__|__/ * QLD 4072, Australia. * | * email: billm@physics.uq.edu.au * | * phone: +61 7 3365 2422 * | * fax: +61 7 3365 1242 Available on WWW at: http://www.physics.uq.edu.au/people/billm/qo.html ------------------------------------------------------------------------------ CONTENTS 0. PROBLEMS 1. ABSTRACTS 2. CONFERENCE ANNOUNCEMENTS 3. WANTED TO BUY/SELL 4. SITUATIONS VACANT 5. MISC NEWS ******************************************************************************* 0. EDITORIAL NOTE Welcome to the first newsletter of this century?. ******************************************************************************* 1. ABSTRACTS TITLE: Signatures of the Pair-Coherent State AUTHORS: A. Gilchrist[1] and W.J. Munro[2] ADDRESSES: [1] School of Computing and Mathematical Sciences, University of Waikato, Hamilton, New Zealand [2] Centre for Laser Science,Department of Physics, University of Queensland, QLD 4072, Brisbane, Australia} WHERE: J. Opt. B: Quantum Semiclass. Opt. 2, 47 (2000). ABSTRACT: We explore in detail the possibility of generating a pair-coherent state in the non-degenerate parametric oscillator when decoherence is included. Such states are predicted in the transient regime in parametric oscillation where the pump mode is adiabatically eliminated. Two specific signatures are examined to indicate whether the state of interest has been generated, the Schr\"odinger cat state---like signatures, and the fidelity. Solutions in a transient regime reveal interference fringes which are indicative of the formation of a Schr\"odinger cat state. The fidelity indicates the purity of our prepared state compared to the ideal pair-coherent state. ________________________________________________________________ TITLE: Entangled SU(2) and SU(1,1) coherent states AUTHORS: Xiao-Guang Wang [1], Barry C. Sanders [2] and Shao-hua Pan [1] ADDRESSES: [1] Institute of Physics, Chinese Academy of Sciences [2] Department of Physics, Macquarie University, Sydney WHERE: http://xxx.lanl.gov/abs/quant-ph/0001073 ABSTRACT: Entangled SU(2) and SU(1,1) coherent states are developed as superpositions of multiparticle SU(2) and SU(1,1) coherent states. In certain cases, these are coherent states with respect to generalized su(2) and su(1,1) generators, and multiparticle parity states arise as a special case. As a special example of entangled SU(2) coherent states, entangled binomial states are introduced and these entangled binomial states enable the contraction from entangled SU(2) coherent states to entangled harmonic oscillator coherent states. Entangled SU(2) coherent states are discussed in the context of pairs of qubits. We also introduce the entangled negative binomial states and entangled squeezed states as examples of entangled SU(1,1) coherent states. A method for generating the entangled SU(2) and SU(1,1) coherent states is discussed and degrees of entanglement calculated. Two types of SU(1,1) coherent states are discussed in each case: Perelomov coherent states and Barut-Girardello coherent states. ___________________________________________________________________ TITLE: Upper Bound on the region of Separable States near the Maximally Mixed State AUTHORS: P. Deuar, W. J. Munro and K. Nemoto ADDRESSES: Centre for Laser Science,Department of Physics, University of Queensland, QLD 4072, Brisbane, Australia WHERE: http://xxx.lanl.gov/abs/quant-ph/0002002 ABSTRACT: A lower bound on the amount of noise that must be added to a GHZ-like entangled state to make it separable (also called the random robustness) is found using the transposition condition. The bound is applicable to arbitrary numbers of subsystems, and dimensions of Hilbert space, and is shown to be exact for qubits. The new bound is compared to previous such bounds on this quantity, and found to be stronger in all cases. It implies that increasing the number of subsystems, rather than increasing their Hilbert space dimension is a more effective way of increasing entanglement. An explicit decomposition into an ensemble of separable states, when the state is not entangled,is given for the case of qubits. ******************************************************************************* 2. CONFERENCES / WORKSHOPS ***************************************************************************** 4. SITUATIONS VACANT MACQUARIE UNIVERSITY DIVISION OF INFORMATION & COMMUNICATION SCIENCES Department of Physics Research Fellow in Theoretical Physics (Full-time (fixed-term)) Ref. 18814 The Quantum Optics Group is seeking to appoint a Research Fellow for a project on quantum networks and quantum interferometry. This project is one of several leading research areas in the group, including quantum information, quantum electrodynamics in confined regions and Bose-Einstein condensation of dilute atomic gases. This project is an ambitious application of Lie group methods to complex quantum networks, including quantum interferometers, quantum cryptography, quantum computing and quantum state engineering. The appointee will conduct research on this project but will also have time to engage in other research endeavours. The appointee is expected to present regular seminars and assist with postgraduate and honours supervision. Applicants must have a PhD (or equivalent) or postdoctoral research achievements in a relevant area of theoretical physics or mathematical physics such as quantum optics or Lie group theory. Applicants must demonstrate achievements in the application of Lie group methods to theoretical physics. Experience with computer programming, including both numerical analysis and algebraic computing, is essential. Preference will be given to applicants with familiarity with interferometry, methods for generating entangled states, quantum information theory, geometric phase and generalised coherent state representations. All enquiries concerning your application and further information about the position should be directed to Associate Professor Barry Sanders on (02) 9850 8935 or e-mail barry.sanders@mq.edu.au and details of research activities and members of the group may be accessed via the web page www.physics.mq.edu.au/~barry/ The position is available on a full-time (fixed-term) basis for a period of two years with the possibility of further appointment subject to funding and performance. Appointment will be subject to the satisfactory completion of a probationary period of three months. Salary range: Level A (Associate Lecturer) $34,647 to $47,019 per annum; an appointee with a PhD will be appointed to a minimum of Point 6 on the salary scale, at $43,803 per annum, plus superannuation. (Under review, under a new Enterprise Agreement expected to be made early in 2000). Applications including full curriculum vitae and quoting the reference number, visa status, and the names and addresses of three referees (including e-mail address) should be forwarded to the Recruitment Manager, Personnel Office, Macquarie University, NSW 2109 by 2 March 2000. Applications will not be acknowledged unless specifically requested. Women are particularly encouraged to apply Equal Employment Opportunity and No Smoking in the Workplace are University Policies. www.pers.mq.edu.au __________________________________________________________________________ ARC RESEARCH FELLOW (Level A) (3Years Fixed Term) EXPERIMENTAL ATOM OPTICS Centre for Laser Science/Department of Physics A vacancy exists for an ARC Research Fellow, three years fixed term, to work with Professor Halina Rubinsztein-Dunlop and A/Professor Norman Heckenberg on the Australian Research Council funded project "Decoherence in Quantum Chaos". The successful candidate must have a PhD in experimental atom optics, or have a demonstrated research record in this area. Experience with numerical modelling will be an advantage. The successful candidate will be required to maintain and further develop a Rb magneto-optical trap and devise and carry out experiments to investigate quantum decoherence in the dynamics of trapped laser cooled atoms. Salary is in the range A$41,199 - A$45,911 per annum. Applications should be sent to Centre for Laser Science/Department of Physics, The University of Queensland, St Lucia Qld 4072. Applicants should arrange for two letters of reference to be sent to the same address. Further details may be obtained from jo@physics.uq.edu.au. Closing date for applications is 15 February 2000. _________________________________________________________________________ ARC Postdoctoral Research Associate Centre for Micro-Photonics, School of Biophysical Sciences & Electrical Engineering An enthusiastic and capable Postdoctoral Research Associate is now sought to work on a new research program "High density optical storage" in the Centre for Micro-Photonics at Swinburne University of Technology. The new research field straddles the disciplines of physics, optics, laser technology, and chemistry and material sciences. The focus of the investigation is to develop a new method for high density optical storage in photo-sensitive polymer materials. The Postdoctoral Research Associate will be engaged on a full time basis, responsible for developing novel polymer materials for high density optical data storage and other applications in the Centre. The position is funded by the Australian Research Council. Applicants must have a PhD in physics or related branches of science or engineering or have qualifications and experience equivalent to this. Excellent research experience in photo-sensitive polymer materials (i.e. photorefractive and photochromic) and in operating ultrashort pulsed lasers is essential. Experience in fibre-optical pulsed lasers and in laser trapping is highly desirable. The closing date for application is Feb. 11 Feb 2000. For further information please contact Professor Min Gu on telephone 61-3-92148776 or 92145435 (mgu@swin.edu.au) or Dr. Xiaosong Gan on telephone 61-3-92148675 (xgan@swin.edu.au), or visit web site http://www.swin.edu.au/corporate/hr/posvac/external.htm (ref. No 21914) for the job description. _____________________________________________________________________ POSTDOCTORAL RESEARCH ASSOCIATE POSITIONS AND PHD SCHOLARSHIPS Centre For Quantum Computer Technology , Australia (Academic) The Australian Centre for Quantum Computer (see article in PHYSICS WORLD, January 2000 p.9) undertakes research on the physics and technology of building, at the atomic level, a solid state quantum computer in silicon. Established in January 2000 through funds from the Australian Research Council and participating institutions, the Centre has nodes at the University of New South Wales, University of Queensland and University of Melbourne, and maintains a substantive collaboration with Los Alamos National Laboratory (USA). The Centre encompasses major research infrastructure including an extensive semiconductor nanofabrication facility, ion implantation, crystal growth, surface analysis and laser physics. 6 POSTDOCTORAL RESEARCH ASSOCIATE (PDRA) POSITIONS - Fixed Term 2-3 years. PDRA - SCANNING TUNNELING MICROSCOPY (Located at UNSW) We seek an experienced PDRA with a strong background in UHV STM. Knowledge of the atomic imaging of silicon surfaces and in particular STM lithography is highly desirable. PDRA - SCANNING PROBE MICROSCOPY (Located at Univ.of Melbourne) We seek a motivated individual with a strong background in scanning probe microscopy and AFM for atomic scale imaging. UHV surface science experience will be highly regarded. PDRA - SILICON MOLECULAR BEAM EPITAXIAL GROWTH (Located at UNSW) We seek a recent physics/engineering PhD or PDRA with a background in semiconductor crystal growth. Experience is desirable in one or more of: UHv, MBE in Si and/or GaAs. PDRA - SEMICONDUCTOR NANOFABRICATION & MEASUREMENT (Located at UNSW) We seek a recent physics/engineering PhD with a background in nanostructure fabrication and measurement. Experience in EBL and/or single electron transistors is highly desirable. PDRA - ION IMPLANTATION (Located at Univ of Melbourne) We seek a motivated individual with experience in high energy (MeV) and low energy (keV) ion implantation doping. Experience in single ion machining & FIB technology is desirable. PDRA - QUANTUM COMPUTAION THEORY (Located at Univ. of Melbourne) We seek a motivated individual to work closely with experimentalists on theory underpinning solid state quantum computation. Areas include: decoherence and error correction, quantum information theory, mesoscopic physics, NMR quantum computing and quantum algorithms. PHD SCHOLARSHIPS 7 Positions - 3 at UNSW; 2 at Univ. Queensland; 2 at Univ. Melbourne Scholarships covering both University fees and living expenses are available for Australian and International candidates. Further details can be found at the website listed below. Closing date for PDRA's: 30 April 2000 Closing date for PhDs: Until Filled. Contact details :For salary levels, position descriptions, selection criteria and application procedure, see our web-site; www.snf.unsw.edu.au or email. Centre Secretariat: email renata.jones@unsw.edu.au ****************************************************************************** 5. MISC NEWS