Physical Review A $(document).ready(function(){ $("form#vols select.volume").change(function() { window.location = $("form#vols").attr("action") + "/" + $.trim($("form#vols select.volume").val()); }); }); $(document).ready(function(){ initMenus('.menu-call'); initTabs('#tabsearch', 1); initTabs('#tabcontent', 1); if(location.hash){ $("a"+location.hash+"-link").click(); } initShadows(); initCitationSearchbox("#tabsearch-citation"); });   American Physical Society   RSS Feeds | Email Alerts  Physical Review Letters Reviews of Modern Physics Physical Review A Physical Review B Physical Review C Physical Review D Physical Review E Physical Review ST: Accelerators and Beams Physical Review ST: Physics Education Research Physical Review Online Archive Physics - Spotlighting Exceptional Research Physical Review Focus Virtual Journals in Science and Technology Annual Index
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APS » Journals » Physical Review A Physical Review A Welcome RapidCommunications RecentPapers AcceptedPapers About Physical Review A Physical Review A provides a dependable resource of worldwide developments in the rapidly evolving area of atomic, molecular and optical physics and related fundamental concepts. The journal contains articles on quantum mechanics including quantum information theory, atomic and molecular structure and dynamics, collisions and interactions (including interactions with surfaces and solids), clusters (including fullerenes), atomic and molecular processes in external fields, matter waves (including Bose-Einstein condensation) and quantum optics. New sections on quantum communication, computation, cryptography and matter waves are growing rapidly. More...  Kaleidoscope Image from "Anyon statistics with continuous variables"Read Article | More Kaleidoscope Images Editorial: APS now leaves copyright with authors for derivative worksOctober 1, 2008When you submit an article to an APS journal, we ask you to sign our copyright form. It transfers copyright for the article to APS, but keeps certain rights for you, the author. We have recently changed the form to add the right to make ‘‘derivative works’’ that reuse parts of the article in a new work. The importance of this change is discussed below.Read More | More EditorialsEditorial: Physics - spotlighting exceptional researchSeptember 15, 2008
Information overload is everywhere, and physicists have not escaped. APS alone publishes over 18,000 articles a year, and lurking within them are some truly exceptional papers that every physicist should know about. How can we most effectively bring the best in all of the Physical Review journals to the wider notice of working physicists? Today is the formal debut of a new free online publication called Physics. Available in preliminary form since July, this new venture offers expert-written commentary articles that highlight and provide context for a select group of papers published by APS and occasionally others. Read More | More EditorialsPRA introduces KaleidoscopeAugust 13, 2008Images from recently published papers are now featured on our web site. Selections will be based on aesthetics; in making our selection we look for attractive and interesting graphics. The image will be identified by the title of the paper; there will also be a link to the article. The image itself may be slightly modified. Recently published images will appear on the main web site for approximately one month, after which they will remain available in an archive.Read More | More News/AnnouncementsAPS seeks new PRA Assistant EditorApril 16, 2008The editors of Physical Review A seek a dynamic and personable colleague to join our team at the American Physical Society Editorial Office.
Read More | More News/Announcements  Physical Review Focus: Molecule in a Cage January 8, 2009A hydrogen molecule trapped in a carbon cage is restricted to discrete energies of linear and rotational motion, an unusually clean demonstration of the wave nature of molecules.Read More |More Focus Articles Timeline The timeline features events related to the Physical Review and Physical Review Letters, as well as seminal developments in physics after 1893. We also list a few important papers published by the journals. Each week, papers published in PRL will be highlighted separately as Milestone Letters. 1947: Shelter Island Conference1965: Cosmic microwave background2006: Free to Read Complete Timeline >   Recently published Rapid Communications in Physical Review A. Fundamental concepts Quantum information Atomic and molecular collisions and interactions Atomic and molecular processes in external fields, including interactions with strong fields and short pulses Matter waves Quantum optics, physics of lasers, nonlinear optics, classical optics Fundamental concepts Detection of continuous variable entanglement without coherent local oscillators Andrew J. Ferris, Murray K. Olsen, Eric G. Cavalcanti, and Matthew J. Davis We propose three criteria for identifying continuous variable entanglement between two many-particle systems with no restrictions on the quantum state of the local oscillators used in the measurements. Mistakenly asserting a coherent state for the local oscillator can lead to incorrectly identifying... [Phys. Rev. A 78, 060104 ] Published Wed Dec 31, 2008Read articleCasimir effect for massless fermions in one dimension: A force-operator approach Dina Zhabinskaya, Jesse M. Kinder, and E. J. Mele We calculate the Casimir interaction between two short-range scatterers embedded in a background of one-dimensional massless Dirac fermions using a force-operator approach. We obtain the force between two finite-width square barriers and take the limit of zero width and infinite potential strength t... [Phys. Rev. A 78, 060103 ] Published Tue Dec 30, 2008Read articleFull quantum reconstruction of vortex states I. Rigas, L. L. Sánchez-Soto, A. B. Klimov, J. Řeháček, and Z. Hradil We propose a complete tomographic reconstruction of vortex states carrying orbital angular momentum. The scheme determines the angular probability distribution of the state at different times under free evolution. To represent the quantum state, we introduce a bona fide Wigner function defined on th... [Phys. Rev. A 78, 060101 ] Published Tue Dec 16, 2008Read articleDecoherence as a signature of an excited-state quantum phase transition A. Relaño, J. M. Arias, J. Dukelsky, J. E. García-Ramos, and P. Pérez-Fernández We analyze the decoherence induced on a single qubit by the interaction with a two-level boson system with critical internal dynamics. We explore how the decoherence process is affected by the presence of quantum phase transitions in the environment. We conclude that the dynamics of the qubit change... [Phys. Rev. A 78, 060102 ] Published Tue Dec 16, 2008Read articleQuantum information Quantifying the non-Gaussian character of a quantum state by quantum relative entropy Marco G. Genoni, Matteo G. Paris, and Konrad Banaszek We introduce a measure to quantify the non-Gaussian character of a quantum state: the quantum relative entropy between the state under examination and a reference Gaussian state. We analyze in detail the properties of our measure and illustrate its relationships with relevant quantities in quantum i... [Phys. Rev. A 78, 060303 ] Published Thu Dec 18, 2008Read articleEntanglement trapping in structured environments Bruno Bellomo, Rosario Lo Franco, Sabrina Maniscalco, and Giuseppe Compagno We highlight the direct link between the time-dependent entanglement and single-qubit excited-state population for two independent qubits, each coupled to a zero-temperature bosonic environment. We show that, in environments structured so as to inhibit spontaneous emission, entanglement trapping and... [Phys. Rev. A 78, 060302 ] Published Fri Dec 12, 2008Read articleMultiparticle entanglement under the influence of decoherence O. Gühne, F. Bodoky, and M. Blaauboer We present a method to determine the decay of multiparticle quantum correlations as quantified by the geometric measure of entanglement under the influence of decoherence. With this, we compare the robustness of entanglement in Greenberger-Horne-Zeilinger (GHZ), cluster, W , and Dicke states of fou... [Phys. Rev. A 78, 060301 ] Published Wed Dec 10, 2008Read articleAtomic and molecular collisions and interactions Collision-induced spin depolarization of alkali-metal atoms in cold 3He gas T. V. Tscherbul, P. Zhang, H. R. Sadeghpour, A. Dalgarno, N. Brahms, Y. S. Au, and J. M. Doyle We present a joint experimental and theoretical study of spin depolarization in collisions of alkali-metal atoms with 3He in a magnetic field. A rigorous quantum theory for spin-changing transitions is developed and applied to calculate the spin exchange and spin relaxation rates of Li and K atoms... [Phys. Rev. A 78, 060703 ] Published Wed Dec 31, 2008Read articleEffect of Förster resonances on the excitation statistics of many-body Rydberg systems A. Reinhard, K. C. Younge, and G. Raithel We provide evidence for the dipole blockade of Rydberg excitation by examining the distributions of the number of Rydberg excitations created in ensembles of interacting Rydberg atoms. We show that, over a range of densities, the Rydberg excitation number distributions become significantly narrower ... [Phys. Rev. A 78, 060702 ] Published Thu Dec 18, 2008Read articleInterference effects due to projectile target nucleus scattering in single ionization of H2 by 75-keV proton impact J. S. Alexander, A. C. Laforge, A. Hasan, Z. S. Machavariani, M. F. Ciappina, R. D. Rivarola, D. H. Madison, and M. Schulz Doubly differential cross sections (DDCSs) for single ionization of molecular hydrogen by 75-keV proton impact have been measured and calculated as a function of the projectile scattering angle and energy loss. Interference structures are observed in the scattering angular dependence of the DDCSs,... [Phys. Rev. A 78, 060701 ] Published Wed Dec 3, 2008Read articleAtomic and molecular processes in external fields, including interactions with strong fields and short pulses Retrieving photorecombination cross sections of atoms from high-order harmonic spectra Shinichirou Minemoto, Toshihito Umegaki, Yuichiro Oguchi, Toru Morishita, Anh-Thu Le, Shinichi Watanabe, and Hirofumi Sakai We observe high-order harmonic spectra generated from a thin atomic medium, Ar, Kr, and Xe, by intense 800-nm and 1300-nm femtosecond pulses. A clear signature of a single-atom response is observed in the harmonic spectra. Especially in the case of Ar, a Cooper minimum, reflecting the electronic... [Phys. Rev. A 78, 061402 ] Published Tue Dec 16, 2008Read articleTranslational cooling and storage of protonated proteins in an ion trap at subkelvin temperatures D. Offenberg, C. B. Zhang, Ch. Wellers, B. Roth, and S. Schiller Gas-phase multiply charged proteins have been sympathetically cooled to translational temperatures below 1 K by Coulomb interaction with laser-cooled barium ions in a linear ion trap. In one case, an ensemble of 53 cytochrome c molecules (mass ≃12 390 amu , charge +17e ) w... [Phys. Rev. A 78, 061401 ] Published Mon Dec 1, 2008Read articleComparison of R -dependent ionization and bond softening as mechanisms for creating vibrational coherence in hot molecules L. Fang and G. N. Gibson We compare the vibrational coherence induced by “ R -dependent ionization,” also known as Lochfrass, and bond softening in strong laser fields through numerical simulations. We calculate the pulse-width and intensity dependence of the vibrational amplitude and average internuclear separation at ... [Phys. Rev. A 78, 051402 ] Published Tue Nov 18, 2008Read articleMatter waves Stirring trapped atoms into fractional quantum Hall puddles Stefan K. Baur, Kaden R. Hazzard, and Erich J. Mueller We theoretically explore the generation of few-body analogs of fractional quantum Hall states. We consider an array of identical few-atom clusters (n=2,3,4) , each cluster trapped at the node of an optical lattice. By temporally varying the amplitude and phase of the trapping lasers, one can introd... [Phys. Rev. A 78, 061608 ] Published Wed Dec 31, 2008Read articleCollapse times of dipolar Bose-Einstein condensates C. Ticknor, N. G. Parker, A. Melatos, S. L. Cornish, D. H. O’Dell, and A. M. Martin We investigate the time taken for global collapse by a dipolar Bose-Einstein condensate. Two semianalytical approaches and exact numerical integration of the mean-field dynamics are considered. The semianalytical approaches are based on a Gaussian ansatz and a Thomas-Fermi solution for the shape of ... [Phys. Rev. A 78, 061607 ] Published Wed Dec 17, 2008Read articlePhase separation in a mixture of a Bose-Einstein condensate and a two-component Fermi gas as a probe of Fermi superfluidity S. G. Bhongale and H. Pu We study the phase diagram of the mixture of a Bose-Einstein condensate and a two-component Fermi gas. In particular, we identify the regime where the homogeneous system becomes unstable against phase separation. We show that, under proper conditions, the phase-separation phenomenon can be exploited... [Phys. Rev. A 78, 061606 ] Published Tue Dec 16, 2008Read articleCoherent energy manipulation in single-neutron interferometry S. Sponar, J. Klepp, R. Loidl, S. Filipp, G. Badurek, Y. Hasegawa, and H. Rauch We have observed the stationary interference oscillations of a triple-entangled neutron state in an interferometric experiment. Time-dependent interaction with two radio-frequency fields enables coherent manipulation of an energy degree of freedom in a single neutron. The system is characterized by ... [Phys. Rev. A 78, 061604 ] Published Mon Dec 15, 2008Read articleInterference of Bose-Einstein condensates: Quantum nonlocal effects W. J. Mullin and F. Laloë Quantum systems in Fock states do not have a phase. When two or more Bose-Einstein condensates are sent into interferometers, they nevertheless acquire a relative phase under the effect of quantum measurements. The usual explanation relies on spontaneous symmetry breaking, where phases are ascribed ... [Phys. Rev. A 78, 061605 ] Published Mon Dec 15, 2008Read articleRadio-frequency association of heteronuclear Feshbach molecules C. Klempt, T. Henninger, O. Topic, M. Scherer, L. Kattner, E. Tiemann, W. Ertmer, and J. J. Arlt We present a detailed analysis of the production efficiency of weakly bound heteronuclear 40K87Rb Feshbach molecules using radio-frequency association in a harmonic trap. The efficiency was measured in a wide range of temperatures, binding energies, and radio frequencies. A comprehensive analytica... [Phys. Rev. A 78, 061602 ] Published Thu Dec 4, 2008Read articleTunneling-induced damping of phase coherence revivals in deep optical lattices Uwe R. Fischer and Ralf Schützhold We consider phase coherence collapse and revival in deep optical lattices, and calculate within the Bose-Hubbard model the revival amplitude damping incurred by a finite tunneling coupling of the lattice wells (after sweeping from the superfluid to the Mott phase). Deriving scaling laws for the corr... [Phys. Rev. A 78, 061603 ] Published Thu Dec 4, 2008Read articleAssociation of ultracold double-species bosonic molecules C. Weber, G. Barontini, J. Catani, G. Thalhammer, M. Inguscio, and F. Minardi We report on the creation of heterospecies bosonic molecules, associated from an ultracold Bose-Bose mixture of 41K and 87Rb , by using a resonantly modulated magnetic field close to two Feshbach resonances. We measure the binding energy of the weakly bound molecular states versus the Feshbach fi... [Phys. Rev. A 78, 061601 ] Published Wed Dec 3, 2008Read articleRadio-frequency-induced ground-state degeneracy in a Bose-Einstein condensate of chromium atoms Q. Beaufils, T. Zanon, R. Chicireanu, B. Laburthe-Tolra, E. Maréchal, L. Vernac, J.-C. Keller, and O. Gorceix We study the effect of strong radio-frequency (rf) fields on a Bose-Einstein condensate (BEC) of chromium atoms, in a regime where the rf frequency is much larger than the Larmor frequency. We use the modification of the Landé factor by the rf field to bring all Zeeman states to degeneracy, despite... [Phys. Rev. A 78, 051603 ] Published Thu Nov 20, 2008Read articleQuantum optics, physics of lasers, nonlinear optics, classical optics Two-way transparency in the light-matter interaction: Optical precursors with electromagnetically induced transparency Heejeong Jeong and Shengwang Du We theoretically study classical step-modulated pulse propagation in an optically thick medium with electromagnetically induced transparency (EIT) using a fast Fourier transform and a proposed hybrid-asymptotic analysis. The 100% transmitted leading edge traveling at c consists of Sommerfeld-Brill... [Phys. Rev. A 79, 011802 ] Published Thu Jan 8, 2009Read articleDegenerate perturbation theory describing the mixing of orbital angular momentum modes in Fabry-Perot cavity resonators David H. Foster, Andrew K. Cook, and Jens U. Nöckel We present an analytic perturbation theory which extends the paraxial approximation for a common cylindrically symmetric stable optical resonator and incorporates the differential, polarization-dependent reflectivity of a Bragg mirror. The degeneracy of Laguerre-Gauss modes with distinct orbital ang... [Phys. Rev. A 79, 011803 ] Published Thu Jan 8, 2009Read articleLinearly polarized bistable localized structure in medium-size vertical-cavity surface-emitting lasers Xavier Hachair, Giovanna Tissoni, Hugo Thienpont, and Krassimir Panajotov We show that a 40-μm -diameter vertical-cavity surface-emitting laser (VCSEL) is capable of supporting spatially localized structures with linear polarization, orthogonal to the principal polarization. The VCSEL is biased above the lasing threshold and emits a well-defined linear polarization (pri... [Phys. Rev. A 79, 011801 ] Published Tue Jan 6, 2009Read articleMultiple-stream instabilities and soliton turbulence in photonic plasma Dmitry V. Dylov and Jason W. Fleischer We demonstrate weak and strong regimes of optical spatial turbulence by considering the nonlinear interaction of three partially coherent spatial beams. The geometry represents a multiple bump-on-tail instability, allowing an interpretation of nonlinear statistical light as a photonic plasma. For we... [Phys. Rev. A 78, 061804 ] Published Wed Dec 24, 2008Read articleSelf-focusing of few optical cycle pulses A. A. Balakin, A. G. Litvak, V. A. Mironov, and S. A. Skobelev Both analytical and numerical investigation of the structural features of ultrashort-laser-pulse self-focusing is presented. The analysis is performed under sufficiently general assumptions concerning the medium dispersion. It is demonstrated that the wave-field self-focusing proceeds with overtakin... [Phys. Rev. A 78, 061803 ] Published Mon Dec 22, 2008Read articleComputational ghost imaging Jeffrey H. Shapiro Ghost-imaging experiments correlate the outputs from two photodetectors: a high spatial-resolution (scanning pinhole or charge-coupled-device camera) detector that measures a field which has not interacted with the object to be imaged and a bucket (single-pixel) detector that collects a field that h... [Phys. Rev. A 78, 061802 ] Published Thu Dec 18, 2008Read articleDark polariton solitons in semiconductor microcavities A. V. Yulin, O. A. Egorov, F. Lederer, and D. V. Skryabin We report the existence of dark polariton solitons and study their stability and symmetry breaking in semiconductor microcavities operating in the strong-coupling regime. These half-light half-matter solitons are potential candidates for applications in all-optical signal processing. Their excitatio... [Phys. Rev. A 78, 061801 ] Published Fri Dec 5, 2008Read articlePolarized light bursts from kicked quantum rings A. S. Moskalenko and J. Berakdar Nonequilibrium quantum rings emit circular-polarized subterahertz radiation with a polarization degree controllable on nano- to picosecond time scales. This we conclude using a theory developed here for the time-dependent detection of the circular polarization of polychromatic radiations, valid for ... [Phys. Rev. A 78, 051804 ] Published Wed Nov 19, 2008Read article Recently published articles in Physical Review A. See the current issue for more. Quantum optics, physics of lasers, nonlinear optics, classical optics Fundamental concepts Quantum information Atomic and molecular structure and dynamics Atomic and molecular collisions and interactions Atomic and molecular processes in external fields, including interactions with strong fields and short pulses Matter waves Quantum optics, physics of lasers, nonlinear optics, classical optics Two-way transparency in the light-matter interaction: Optical precursors with electromagnetically induced transparency Heejeong Jeong and Shengwang Du  We theoretically study classical step-modulated pulse propagation in an optically thick medium with electromagnetically induced transparency (EIT) using a fast Fourier transform and a proposed hybrid-asymptotic analysis. The 100% transmitted leading edge traveling at c consists of Sommerfeld-Brill... [Phys. Rev. A 79, 011802 ] Published Thu Jan 8, 2009Read articleDegenerate perturbation theory describing the mixing of orbital angular momentum modes in Fabry-Perot cavity resonators David H. Foster, Andrew K. Cook, and Jens U. Nöckel We present an analytic perturbation theory which extends the paraxial approximation for a common cylindrically symmetric stable optical resonator and incorporates the differential, polarization-dependent reflectivity of a Bragg mirror. The degeneracy of Laguerre-Gauss modes with distinct orbital ang... [Phys. Rev. A 79, 011803 ] Published Thu Jan 8, 2009Read articleBessel lattice solitons in competing cubic-quintic nonlinear media Liangwei Dong, Jiandong Wang, Hui Wang, and Guoyan Yin We investigate the existence and stability of spatial optical solitons supported by cylindrical Bessel lattices in a competing cubic-quintic (CQ) nonlinear medium. Various families of solitons, including vortex, multipole, and necklace solitons are presented. Vortex solitons with unit topological ch... [Phys. Rev. A 79, 013807 ] Published Thu Jan 8, 2009Read articleDiscretely tunable optical packet delays using channelized slow light Zhimin Shi (石志敏) and Robert W. Boyd We describe a procedure for increasing the fractional delay (or delay-bandwidth product) of a slow-light system. A broadband input signal is sliced into several frequency bands. The light in each band propagates through a separate channel which possesses a highly reduced group velocity over a narrow... [Phys. Rev. A 79, 013805 ] Published Tue Jan 6, 2009Read articleRealization of coherent optically dense media via buffer-gas cooling Tao Hong, Alexey V. Gorshkov, David Patterson, Alexander S. Zibrov, John M. Doyle, Mikhail D. Lukin, and Mara G. Prentiss We demonstrate that buffer-gas cooling combined with laser ablation can be used to create coherent optical media with high optical depth and low Doppler broadening that offers metastable states with low collisional and motional decoherence. Demonstration of this generic technique opens pathways to c... [Phys. Rev. A 79, 013806 ] Published Tue Jan 6, 2009Read articleFundamental concepts Control of state and state entanglement with a single auxiliary subsystem R. Rossi, A. R. Bosco de Magalhães, J. G. Peixoto de Faria, and M. C. Nemes We present a strategy to control the evolution of a quantum system using a single auxiliary subsystem. Two applications are given, one which allows for state preservation and another which controls the degree of entanglement of a given initial state. [Phys. Rev. A 79, 012103 ] Published Thu Jan 8, 2009Read articleFidelity of asymmetric dephasing channels J. Dajka, M. Mierzejewski, and J. Łuczka We study the properties of the fidelity of one-qubit operations in a noisy channel and reveal its properties in dependence on coupling to the outer environment. We show that for an asymmetric qubit-environment coupling, the fidelity can be improved by a tuning of the external parameters acting on th... [Phys. Rev. A 79, 012104 ] Published Thu Jan 8, 2009Read articleHamiltonians generating optimal-speed evolutions Ali Mostafazadeh We present a simple derivation of the formula for the Hamiltonian operator(s) that achieve the fastest possible unitary evolution between given initial and final states. We discuss how this formula is modified in pseudo-Hermitian quantum mechanics and provide an explicit expression for the most gene... [Phys. Rev. A 79, 014101 ] Published Tue Jan 6, 2009Read articleQuantum information Generation of atom-atom correlations inside and outside the mutual light cone Juan León and Carlos Sabín We analyze whether a pair of neutral two level atoms can become entangled in a finite time while they remain causally disconnected. The interaction with the electromagnetic field is treated perturbatively in the electric dipole approximation. We start from an initial vacuum state and obtain the fina... [Phys. Rev. A 79, 012304 ] Published Thu Jan 8, 2009Read articleDirect observation of quantum criticality in Ising spin chains Jingfu Zhang, Fernando M. Cucchietti, C. M. Chandrashekar, Martin Laforest, Colm A. Ryan, Michael Ditty, Adam Hubbard, John K. Gamble, and Raymond Laflamme We use NMR quantum simulators to study antiferromagnetic Ising spin chains undergoing quantum phase transitions. Taking advantage of the sensitivity of the systems near criticality, we detect the critical points of the transitions using a direct measurement of the Loschmidt echo. We test our simulat... [Phys. Rev. A 79, 012305 ] Published Thu Jan 8, 2009Read articlePairing in fermionic systems: A quantum-information perspective Christina V. Kraus, Michael M. Wolf, J. Ignacio Cirac, and Géza Giedke The notion of “paired” fermions is central to important condensed-matter phenomena such as superconductivity and superfluidity. While the concept is widely used and its physical meaning is clear, there exists no systematic and mathematical theory of pairing that would allow us to unambiguously c... [Phys. Rev. A 79, 012306 ] Published Thu Jan 8, 2009Read articleUnambiguous comparison of unitary channels Michal Sedlák and Mário Ziman We address the problem of an unambiguous comparison of a pair of unknown qudit unitary channels. Using the framework of process positive operator valued measures we characterize all solutions and identify the optimal ones. We prove that the entanglement is the key ingredient in designing the optimal... [Phys. Rev. A 79, 012303 ] Published Wed Jan 7, 2009Read articleAtomic and molecular structure and dynamics Prospects for application of ultracold Sr2 molecules in precision measurements S. Kotochigova, T. Zelevinsky, and Jun Ye Precision measurements with ultracold molecules require development of robust and sensitive techniques to produce and interrogate the molecules. With this goal, we theoretically analyze factors that affect frequency measurements between rovibrational levels of the Sr2 molecule in the electronic gr... [Phys. Rev. A 79, 012504 ] Published Thu Jan 8, 2009Read articleTheoretical study of low-lying electronic terms and transition moments for HfF+ for the electron electric-dipole-moment search A. N. Petrov, N. S. Mosyagin, and A. V. Titov We report ab initio relativistic 20-electron correlation calculations of electric-dipole transition moments for nine low-lying electronic states of HfF+ , which it is suggested to be used in experiments to search for the electric-dipole moment of the electron. Radiative lifetimes for the lowest vib... [Phys. Rev. A 79, 012505 ] Published Thu Jan 8, 2009Read articleCoupled nuclear and electronic ground-state motion from variational reduced-density-matrix theory with applications to molecules with floppy or resonant hydrogens Eugene Kamarchik and David A. Mazziotti The variational two-electron reduced-density-matrix (2RDM) method for electronic systems [Phys. Rev. Lett. 93, 213001 (2004)] is extended to compute ground-state distributions of electrons and hydrogen nuclei in molecules beyond the Born-Oppenheimer approximation. While traditional methods for nucle... [Phys. Rev. A 79, 012502 ] Published Wed Jan 7, 2009Read articleDensity gradients for the exchange energy of electrons in two dimensions Stefano Pittalis, Esa Räsänen, José G. Vilhena, and Miguel A. Marques We derive a generalized gradient approximation to the exchange energy to be used in density functional theory calculations of two-dimensional systems. This class of approximations has a long and successful history, but it has not yet been fully investigated for electrons in two dimensions. We follow... [Phys. Rev. A 79, 012503 ] Published Wed Jan 7, 2009Read articleUse of the differential virial theorem to estimate the spatial variation of the exchange-correlation force −∂VXC(r)∕∂r in the ground states of the spherical atoms He and Be Ferenc Bogár, Ferenc Bartha, and Norman H. March We use the differential virial theorem (DVT) directly to display the approximate spatial dependence of the exchange-correlation (XC) force in He and Be, applying an exact integral constraint on the XC force, recently established by March and Nagy. In He, an analytic ground-state density n(r) , comb... [Phys. Rev. A 79, 014501 ] Published Tue Jan 6, 2009Read articleAtomic and molecular collisions and interactions Elastic differential cross sections for electron scattering from SF6 and CS2 K. G. Bhushan, K. C. Rao, S. C. Gadkari, J. V. Yakhmi, and S. K. Gupta Elastic differential cross sections have been measured for electron- SF6 and electron- CS2 collisions in the energy range from 30 eV to 500 eV using a high resolution electron spectrometer. The measured cross sections have been put on an absolute scale using the relat... [Phys. Rev. A 79, 012702 ] Published Wed Jan 7, 2009Read articleAtomic and molecular processes in external fields, including interactions with strong fields and short pulses Semiclassical propagation method for tunneling ionization Ilya I. Fabrikant and Gordon A. Gallup We apply the semiclassical propagation technique to tunneling ionization in atomic and molecular systems. Semiclassical wave functions and the tunneling flux are calculated from the solution of the classical equations of motion in the complex time plane. We illustrate this method by rederiving the k... [Phys. Rev. A 79, 013406 ] Published Thu Jan 8, 2009Read articleThree-wire magnetic trap for direct forced evaporative cooling Shengwang Du and Eun Oh We propose a simple three-wire-based magnetic trap potential for direct forced evaporative cooling of neutral atoms without using induced spin-flip technologies. We have devised a method for controlling the trap depth without sacrificing its frequencies by only varying wire currents and external mag... [Phys. Rev. A 79, 013407 ] Published Thu Jan 8, 2009Read articleOptimal geometry for efficient loading of an optical dipole trap Andrzej Szczepkowicz, Leszek Krzemień, Adam Wojciechowski, Krzysztof Brzozowski, Michael Krüger, Michał Zawada, Marcin Witkowski, Jerzy Zachorowski, and Wojciech Gawlik One important factor which determines efficiency of loading cold atoms into an optical dipole trap from a magneto-optical trap is the distance between the trap centers. By studying this efficiency for various optical trap depths (2–110 mK) we find that for optimum dipole trap loading, lon... [Phys. Rev. A 79, 013408 ] Published Thu Jan 8, 2009Read articleac Stark shift of the Cs microwave atomic clock transitions P. Rosenbusch, S. Ghezali, V. A. Dzuba, V. V. Flambaum, K. Beloy, and A. Derevianko We analyze the ac Stark shift of the Cs microwave atomic clock transition theoretically and experimentally. Theoretical and experimental data are in good agreement with each other. Results indicate the absence of a magic wavelength at which there would be no differential shift of the clock states ha... [Phys. Rev. A 79, 013404 ] Published Wed Jan 7, 2009Read articleCold guided beams of water isotopologs M. Motsch, L. D. van Buuren, C. Sommer, M. Zeppenfeld, G. Rempe, and P. W. Pinkse Electrostatic velocity filtering and guiding is an established technique to produce high fluxes of cold polar molecules. In this paper we clarify different aspects of this technique by comparing experiments to detailed calculations. In the experiment, we produce cold guided beams of the three water ... [Phys. Rev. A 79, 013405 ] Published Wed Jan 7, 2009Read articleMatter waves Vortex-lattice pinning in two-component Bose-Einstein condensates M. P. Mink, C. Morais Smith, and R. A. Duine We investigate the vortex-lattice structure for single- and two-component Bose-Einstein condensates in the presence of an optical lattice, which acts as a pinning potential for the vortices. The problem is considered in the mean-field quantum Hall regime, which is reached when the rotation frequency... [Phys. Rev. A 79, 013605 ] Published Wed Jan 7, 2009Read article Papers recently accepted for publication in Physical Review A (view more). Fundamental concepts Quantum information Atomic and molecular structure and dynamics Atomic and molecular collisions and interactions Atomic and molecular processes in external fields, including interactions with strong fields and short pulses Matter waves Quantum optics, physics of lasers, nonlinear optics, classical optics Fundamental concepts Tight correlation function Bell inequality for multipartite d-dimensional systems JingLing Chen and DongLing Deng We generalize the correlation functions of the Clauser-Horne-Shimony-Holt (CHSH) inequality to multipartite d-dimensional systems. All the Bell inequalities based on this generalization take the same simple form as the CHSH inequality. For small systems, numerical results show that the new inequalities are tight and we believe this is also valid for higher dimensional systems. Moreover, the new inequalities are relevant to the previous ones and for bipartite system, our inequality is equivalent to the Collins-Gisin-Linden-Masser-Popescu (CGLMP) inequality. Accepted Thu Jan 8, 2009Inadequacy of a classical interpretation of quantum projective measurements via Wigner functions Amir Kalev, Ady Mann, Pier A. Mello and Michael Revzen We study the possibility of giving a classical interpretation to quantum projective measurements for a particle described by a pure Gaussian state whose Wigner function is non-negative. We analyze the case of a projective measurement which gives rise to a proper Wigner function, i.e., taking on, as its values, the eigenvalues of the projector. We find that, despite having this property, this kind of projector produces a state whose Wigner function ceases to be non-negative and hence precludes its interpretation as a classical probability density. We also study the general case in which the projected state has a non-negative Wigner function; but then we find that the Wigner function of the projector is not a proper one. Thus, we conclude that a non-negative Wigner function is inadequate to serve as a hidden variable model for quantum processes in which projective measurements take place. Accepted Thu Jan 8, 2009Entropic uncertainty relation for mutually unbiased bases Wu Shengjun, Yu Sixia and Klaus Molmer We derive new inequalities for the probabilities of projective measurements in mutually unbiased bases of a qudit system. These inequalities lead to wider ranges of validity and tighter bounds on entropic uncertainty inequalities previously derived in the literature. Accepted Thu Jan 8, 2009Quantum information Compact Toffoli gate using weighted graph states M. S. Tame, S. K. Ozdemir, M. Koashi, N. Imoto and M. S. Kim We introduce three compact graph states that can be used to perform a measurement-based Toffoli gate. Given a weighted graph of six, seven or eight qubits, we show that success probabilities of 1/4, 1/2 and 1 respectively can be achieved. Our study puts a measurement-based version of this important quantum logic gate within the reach of current experiments. As the graphs are setup-independent, they could be realized in a variety of systems, including linear optics and ion-traps. Accepted Wed Jan 7, 2009Optimized quantum random walk search algorithms on the hypercube V. Potocek, A. Gabris, T. Kiss and I. Jex Shenvi, Kempe and Whaley's quantum random-walk search (SKW) algorithm [Phys. Rev. A 67, 052307 (2003)] is known to require O(N) number of oracle queries to find the marked element, where N is the size of the search space. The overall time complexity of the SKW algorithm differs from the best achievable on a quantum computer only by a constant factor. We present improvements to the SKW algorithm which yield significant increase in success probability, and an improvement on query complexity such that the theoretical limit of a search algorithm succeeding with probability close to one is reached. We point out which improvement can be applied if there is more than one marked element to find. Accepted Tue Jan 6, 2009Atomic and molecular structure and dynamics Discontinuity of the chemical potential in reduced density-matrix functional theory for open shell systems N. Helbig, N. N. Lathiotakis and E. K. U. Gross We employ reduced density-matrix functional theory in the calculation of the fundamental gap of open-shell systems. The formula for the calculation of the fundamental gap is derived with special attention to the spin of the neutral and the charged systems. We discuss the effects of different functionals as well as the changes due to different basis sets. Also, we investigate the importance of varying the natural orbitals for the calculation of the fundamental gap. Accepted Wed Jan 7, 2009Atomic and molecular collisions and interactions Off the-energy shell effect in the dissociative recombination of HD^{+} H. Takagi, S. Hara and H. Sato The Lippmann-Schwinger (LS) equation for the K matrix is numerically solved for the collision of HD+ + e interacting by the configuration interaction (CI). The realistic CI strength is deduced from ab-initio calculation of electron scattering. The LS equation is extended to the negative collision energies in the context of multichannel quantum defect theory (MQDT) for the dissociative recombination (DR). A decoupling property is shown for the LS equation, which is useful for reducing the amount of the calculation. The Chebyshev quadrature is employed for the calculation and fully converged result has been obtained. Using the result with the MQDT, The DR cross section of HD+ is obtained. It has turned out that the off-the-energy-shell contribution is indispensable to understand the DR. The contribution from the negative energies largely affects the low energy DR. The DR at low energy is induced by the indirect process with rotational excitation. The separable approximation on the CI is examined for the realistic CI strength. This approximation has turned out to be inadequate for the DR of HD+. The calculated rate coefficient reproduces the experiment both on the absolute magnitude and resonance structure. The off-the-energy shell contribution largely affects on the initial vibrational state (v+) dependence. This contribution increases the rate coefficient for v+=0 and decreases for v+=2. Accepted Wed Jan 7, 2009Collisions of paramagnetic molecules in magnetic fields: An analytic model based on Fraunhofer diffraction of matter waves Mikhail Lemeshko and Bretislav Friedrich We investigate the effects of a magnetic field on the dynamics of rotationally inelastic collisions of open-shell molecules (2S, 3S, and 2P) with closed-shell atoms. Our treatment makes use of the Fraunhofer model of matter wave scattering and its recent extension to collisions in electric [M. Lemeshko and B. Friedrich, J. Chem. Phys. 129, 024301 (2008)] and radiative fields [M. Lemeshko and B. Friedrich, Int. J. Mass. Spec. in press (2008)]. A magnetic field aligns the molecule in the space-fixed frame and thereby alters the effective shape of the diffraction target. This significantly affects the differential and integral scattering cross sections. We exemplify our treatment by evaluating the magnetic-field-dependent scattering characteristics of the He - CaH (X 2S+), He - O2 (X 3S-) and He - OH (X 2PW) systems at thermal collision energies. Since the cross sections can be obtained for different orientations of the magnetic field with respect to the relative velocity vector, the model also offers predictions about the frontal-versus-lateral steric asymmetry of the collisions. The steric asymmetry is found to be almost negligible for the He - OH system, weak for the He - CaH collisions, and strong for the He - O2. While odd DM transitions dominate the He - OH (J=3/2,f J, e/f) integral cross sections in a magnetic field parallel to the relative velocity vector, even DM transitions prevail in the case of the He - CaH (X 2S+) and He - O2 (X 3S-) collision systems. For the latter system, the magnetic field opens inelastic channels that are closed in the absence of the field. These involve the transitions N=1, J=0 N, J with J=N. Accepted Tue Jan 6, 2009Atomic and molecular processes in external fields, including interactions with strong fields and short pulses Comparative study of strong field ionization in laser irradiated F_{2} molecules and other diatomic molecules: Density functional-theory based molecular strong field approximation Vladimir I. Usachenko, Pavel E. Pyak and Vyacheslav V. Kim he puzzling phenomenon of no suppression observed in experiments on strong-field ionization of laser-irradiated diatomic $F_{2}$ molecule (as compared to its atomic counterpart $Ar$ of nearly equal ionization potential) is addressed within the {\it velocity-gauge} (VG) formulation of molecular {\it strong-field approximation} (SFA). The approach essentially exploits the {\it density functional theory} (DFT) method applied for numerical composition of initial (laser-free) molecular states using the model $LB_{\alpha}$ intramolecular binding potential, which incorporates both the {\it exchange} and {\it correlation} LSDA-potentials and also provides a correct reproducing all initial (laser-free) molecular valence shells and respective binding energies. Unlike the respective results of earlier alternative strong-field considerations (all predicting a high suppression in $F_{2}$ ionization), our DFT-SFA based calculation results unambiguously demonstrate no suppression in strong-field ionization of $F_{2}$ versus its atomic ($Ar$) and molecular ($N_{2}$) counterparts. Our presented results also suggest that predominant contribution to $F_{2}$ ionization is to be always from the $1{\pi_g}$ {\it highest occupied molecular orbital} (HOMO, corresponding to the outermost valence shell) and allow for quite a transparent physical interpretation. Namely, the phenomenon of no suppression in $F_{2}$ ionization, is just explained by the {\it closed-shell} nature of its $1{\pi_g}$ HOMO (and, thus, by its a substantially more enhanced and pronounced electron-correlated response to incident laser field). Quantitatively, the latter becomes manifest through equal contributions from the correlation and exchange parts of intramolecular LSDA-potential to $F_{2}$ and $N_{2}$ valence shells, in contrast to $O_{2}$ valence shells, to which the exchange part of LSDA-potential proved to contribute predominantly resulting in a high suppression of ionization relative to atomic counterpart $Xe$. Accepted Thu Jan 8, 2009Photodissociation dynamics of rare gas ionic trimers Daniel Hrivnak, Rene Kalus and Florent Xavier Gadea Semiclassical mean-field dynamics approach is used in combination with diatomics-in-molecules methods to study photodissociation of ionized trimers of argon, krypton, and xenon. The dynamics of photodissociation is analyzed in terms of the kinetic energy distribution of ionic and neutral fragments, fragmentation patterns, and fragmentation times. Particular attention is paid to the effect of the spin-orbit coupling and clusters temperature. Theoretical results are thoroughly compared with recent experimental as well as theoretical data. Accepted Wed Jan 7, 2009Landscape of unitary transformations in controlled quantum dynamics Ho TakSan, Jason Dominy and Herschel Rabitz We consider the control problem of generating unitary transformations, which is especially relevant to current research in quantum information processing and computing, in contrast to the usual state-to-state or the more general observable expectation value control problems. A previous analysis of optimal control landscapes for unitary transformations from a kinematic perspective in the finite-dimensional unitary matrices is extended to a dynamical one in the infinite-dimensional function space of the time-dependent external field. The underlying dynamical landscape is defined as the Frobenius square norm of the difference between the control unitary matrix and the target matrix. A non-singular adaptation matrix is introduced to provide additional freedom for exploring and manipulating key features, specifically the slope and curvature, of the control landscapes. The dynamical analysis reveals many essential geometric features of optimal control landscapes for unitary transformations, including bounds on the local landscape slope and curvature. Close examination of the curvatures at the critical points shows that the unitary transformation control landscapes are free of local traps and proper choices of the adaptation matrix may facilitate the search for optimal control fields producing desired unitary transformations, in particular, in the neighborhood of the global extrema. Accepted Tue Jan 6, 2009Matter waves Quenches in quantum many body systems: One dimensional Bose Hubbard model reexamined Guillaume Roux When a quantum many-body system undergoes a quench, the time-averaged density-matrix [`(r)] governs the time-averaged expectation value of any observable. It is therefore the key object to look at when comparing results with equilibrium predictions. We show that the weights of [`(r)] can be efficiently computed with Lanczos diagonalization for relatively large Hilbert spaces. As an application, we investigate the crossover from perturbative to non-perturbative quenches in the non-integrable Bose-Hubbard model: on finite systems, an approximate Boltzmann distribution is observed for small quenches, while for larger ones the distributions do not follow standard equilibrium predictions. Studying thermodynamical features, such as the energy fluctuations and the entropy, shows that [`(r)] bears a memory of the initial state. Accepted Thu Jan 8, 2009Ground state energy of the unitary Fermi gas from the \epsilon expansion Yusuke Nishida We update the ground state energy ratio of unitary Fermi gas to noninteracting Fermi gas (x) from the e expansion by including the next-to-next-to-leading-order (NNLO) term near two spatial dimensions. Interpolations of the NNLO e expansions around four and two spatial dimensions with the use of Padé approximants give x 0.3600.020 in three dimensions with the uncertainty due to different interpolation functions. This value is consistent with the previous interpolations of the NLO e expansions x 0.3770.014 in spite of the large NNLO corrections. Accepted Thu Jan 8, 2009Optimizing number squeezing when splitting a mesoscopic condensate Julian Grond, Jorg Schmiedmayer and Ulrich Hohenester We optimize number squeezing when splitting a mesoscopic Bose Einstein condensate. Applying optimal control theory to a realistic description of the condensate allowed us to identify a form of the splitting ramp which drastically outperforms the adiabatic splitting. The results can be interpreted in terms of a generic two-mode model mapped onto a parametric harmonic oscillator. This optimal route to squeezing paves the way to a much longer phase coherence and atom interferometry close to the Heisenberg limit. Accepted Wed Jan 7, 2009Signatures of the superfluid to--Mott insulator transition in cold bosonic atoms in a one dimensional optical lattice S. Ramanan, Tapan Mishra, Meetu Sethi Luthra, Ramesh V. Pai and B. P. Das We study the Bose-Hubbard model using the finite size density matrix renormalization group method. We obtain for the first time a complete phase diagram for a system in the presence of a harmonic trap and compare it with that of the homogeneous system. The superfluid to the Mott insulator phase transition is investigated using different experimental signatures of these phases in quantities such as momentum distribution, visibility, condensate fraction and the total number of bosons at a particular density. The relationships between the various experimental signatures and the phase diagram are highlighted. Accepted Tue Jan 6, 2009Quantum optics, physics of lasers, nonlinear optics, classical optics Dependence of high order harmonic intensity on the length of preformed plasma plumes H. Singhal, V. Arora, B. S. Rao, P. A. Naik, U. Chakravarty, R. A. Khan and P. D. Gupta An experimental study has been carried out on high order harmonic generation from the interaction of 45 fs Ti:sapphire laser pulses with low-excited silver plasma plumes. The dependence of high order harmonic intensity (IH) on the plasma plume length (Lmed) shows slower than quadratic scaling IH nbsp; Lmed^p with 'p' nbsp; 0.9, 0.8 and 0.7 for 21st, 33rd and 41st harmonics respectively. The harmonic intensity is observed to decrease with increasing harmonic order, and this decrease is faster for longer plasma plumes. The results are explained from physical considerations of phase mismatch between the driving laser pulse and the harmonic radiation during propagation, and re-absorption of the harmonic radiation in the plasma plume. Accepted Thu Jan 8, 2009Competition between Raman- and Rayleigh enhanced four wave mixings in attosecond polarization beats Chenli Gan, Yanpeng Zhang, Zhiqiang Nie, Yan Zhao, Lu Keqing, Si Jinhai and Min Xiao Accepted Thu Jan 8, 2009Theory of Cherenkov radiation in periodic dielectric media: Emission spectrum Christian Kremers, Dmitry N. Chigrin and Johann Kroha The Cherenkov radiation is substantially modified in the presence of a medium with a nontrivial dispersion relation. We consider Cherenkov emission spectra of a point or line charge, respectively, moving in general, three- (3D) and two-dimensional (2D) photonic crystals. Exact analytical expressions for the spectral distribution of the radiated power are obtained in terms of the Bloch mode expansion. The resulting expression reduces to a simple contour integral (3D case) or a one-dimensional sum (2D case) over a small fraction of the reciprocal space, which is defined by the generalized Cherenkov condition. We apply our method to a specific case of a line source moving with different velocities in a 2D square-lattice photonic crystal. Our method demonstrates a reasonable agreement with numerically rigorous finite-difference time-domain calculations while being less demanding on computational resources. Accepted Thu Jan 8, 2009Interferometric switching of coherent anti Stokes Raman scattering signals in microscopy Alex Nikolaenko, Vishnu Vardhan Krishnamachari and Eric Olaf Potma Coherent anti-Stokes Raman scattering (CARS) interferometry is used to deplete the anti-Stokes radiation emerging from a tightly focused spot. Near-to-complete depletion of the anti-Stokes radiation is obtained when a phase-controlled local oscillator field at the anti-Stokes frequency is out-of-phase with the induced CARS field in the focal volume. Unlike in traditional interferometry, this depleted energy is not spatially redistributed. A theoretical analysis shows that the energy loss in the anti-Stokes channel is accompanied by an energy gain in the pump and Stokes channels. Interferometric switching of anti-Stokes radiation may offer a route toward developing high resolution CARS microscopy. Accepted Thu Jan 8, 2009Dressed state mixed parity transitions for realizing negative refractive index Clifford M. Krowne and Jian Qi Shen The dressed states that are the linear combinations of two bare levels of an atom (e.g., alkali metallic atom) can be realized by a strong coupling laser beam. As the dressed states have mixed parities, both electric- and magnetic-dipole allowed transitions can occur between the dressed states and a third level with a definite (pure) parity. It is shown that such dressed-state mixed-parity transitions in an atomic vapor can give rise to a negative refractive index. The produced negative refractive index is isotropic with atomic-scale microscopic structure units, and the negative real part can emerge in the optical frequency band. Accepted Wed Jan 7, 2009Spin and orbital Hall effects for diffracting optical beams in gradient index media Konstantin Y. Bliokh and Anton S. Desyatnikov We examine the evolution of paraxial beams carrying intrinsic spin and orbital angular momenta (AM) in gradient-index media. A parabolic-type equation is derived which describes the beam diffraction in curvilinear coordinates accompanying the central ray. The center of gravity of the beam experiences transverse AM-dependent deflections - the spin and orbital Hall effects. The spin Hall effect generates a transverse translation of the beam as a whole, in precise agreement with recent geometrical optics predictions. At the same time, the orbital Hall effect is significantly affected by the diffraction in the inhomogeneous medium and is accompanied by changes in the intrinsic orbital AM and deformations of the beam. Accepted Wed Jan 7, 2009Understanding the nonlinear phase and frequency shift of an ultrashort light pulse induced by an inertial third order optical nonlinearity A. M. Zheltikov Inertia of optical nonlinearity is shown to distort the temporal profile of the intensitydependent phase shift of an ultrashort laser pulse relative to the phase induced by the instantaneous optical nonlinearity. We demonstrate that a weakly inertial optical nonlinearity, whose response time is smaller than the pulse width, tends to red-shift the light field and generates a cubic-phase correction to the quadratic phase, thus complicating the chirp of the spectrally broadened field. For very short light pulses with pulse widths shorter than the response times of optical nonlinearity, the red-shift and cubic-phase terms often dominate the nonlinear phase shift, giving rise to phase profiles significantly different from those induced by instantaneous optical nonlinearity. Accepted Wed Jan 7, 2009Comment on ``Casimir force acting on magnetodielectric bodies embedded in media'' Iver Brevik and Simen A. Ellingsen In a recent paper [C. Raabe and D.-G. Welsch, Phys. Rev. A 71, 013814 (2005)] an electromagnetic energy-momentum tensor is suggested as an alternative to the Abraham-Minkowski tensor and is applied to calculations of Casimir forces in planar geometries. We argue that the universality of the suggested tensor is doubtful; application of the Raabe-Welsch theory to a simple example in classical electrodynamics shows that their proposed tensor is unable to describe the situation in a simple way. We also show that modified Casimir forces acting on the cavity medium as prescribed by these authors suffer from problems of definiteness and peculiar properties which call for experimental support before this theory can be regarded as acceptable. Accepted Wed Jan 7, 2009Sub Rayleigh-diffraction bound quantum imaging Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone and Jeffrey H. Shapiro The spatial resolution of an imaging apparatus is limited by the Rayleigh diffraction bound, a consequence of the imager's finite spatial extent. We show some N-photon strategies that permit resolution of details that are smaller than this bound, attaining either a 1/N enhancement (standard quantum limit) or a 1/N enhancement (Heisenberg-like scaling) over standard techniques. In the incoherent imaging regime, the methods presented are loss resistant, since classical light sources suffice. Our results may be of importance in many applications: microscopy, telescopy, lithography, metrology, etc. Accepted Wed Jan 7, 2009Indistinguishability of independent single photons F. W. Sun and C. W. Wong The indistinguishability of independent single photons is presented by decomposing the single photon pulse into the mixed state of different transform limited pulses. The entanglement between single photons and outer environment or other photons induces the distribution of the center frequencies of those transform limited pulses and makes photons distinguishable. Only the single photons with the same transform limited form are indistinguishable. In details, the indistinguishability of single photons from the solid-state quantum emitter and spontaneous parametric down conversion is examined with two-photon Hong-Ou-Mandel interferometer. Moreover, experimental methods to enhance the indistinguishability are discussed, where the usage of spectral filter is highlighted. Accepted Wed Jan 7, 2009 All Accepted Papers Current Issue Earlier Issues Article Lookup Journal Search Site Search Phys. Rev. Lett. Phys. Rev. A Phys. Rev. B Phys. Rev. C Phys. Rev. D Phys. Rev. E Phys. Rev. ST AB Phys. Rev. ST PER Phys. Rev. (Series I) Phys. Rev. Rev. Mod. Phys. Vol.: Article: or by citation or DOI Search: Abstract/title Author: Full Record: Full Text: Title: Abstract: Cited Author: Collaboration: Affiliation: PACS: Advanced Search Search:
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