We introduce an alternative method based on local quantum uncertainty to measure non-Markovianity for an open quantum system. The local quantum uncertainty proposed by Girolami et al. [Phys. Rev. Lett. 110, 240402 (2013)PRLTAO10.1103/PhysRevLett.110.240402] is defined by the minimum skew information...

[Phys. Rev. A 90, 042101] Published Wed Oct 01, 2014

]]>Quantum memories have been realized in different physical systems, such as atomic ensembles or solid systems. To date, all quantum memories have realized the storage and retrieval of photons encoded using only a two-dimensional space spanned, for example, by the orthogonal polarization states, and h...

[Phys. Rev. A 90, 042301] Published Wed Oct 01, 2014

]]>We present experimental and theoretical results for electron-impact-induced ionization and excitation of helium atoms. Using a high-sensitivity and high-resolution (e,2e) spectrometer, we measured the differential cross sections of ionization-excitation of He to the n=1−5 states of He+ at an impact ...

[Phys. Rev. A 90, 042701] Published Wed Oct 01, 2014

]]>A new way of measuring pair correlations in a system of ultracold fermions in the BCS-BEC crossover is suggested, employing a process analogous to double photoemission known from solid-state physics.

[Phys. Rev. A 90, 043601] Published Wed Oct 01, 2014

]]>Jaynes-Cummings-Hubbard lattices provide unique properties for the study of correlated phases as they exhibit convenient state preparation and measurement, as well as in situ tuning of parameters. We show how to realize charge density and supersolid phases in Jaynes-Cummings-Hubbard lattices in the ...

[Phys. Rev. A 90, 043801] Published Wed Oct 01, 2014

]]>The nonreciprocal propagation of light at the single-photon level is essential for building a quantum network. Bulk optical schemes are lossy and difficulty to integrate onto a chip. We propose a single-photon optical diode and a three-port circulator without a magnetic field by coupling an unbalanc...

[Phys. Rev. A 90, 043802] Published Wed Oct 01, 2014

]]>Two aspects of the classic two-level Landau-Zener (LZ) problem are considered. First, we address the LZ problem when one or both levels decay, i.e., ɛj(t)→ɛj(t)−iΓj/2. We find that if the system evolves from an initial time −T to a final time +T such that |ɛ1(±T)−ɛ2(±T)| is not too large, the LZ sur...

[Phys. Rev. A 90, 032116] Published Tue Sep 30, 2014

]]>We determine the role of entanglement for nonlocal memory effects induced by initial correlations in a composite environment. The dephasing dynamics of two two-level systems which are coupled locally to an environment consisting of nonlocally correlated field modes is studied with respect to the occ...

[Phys. Rev. A 90, 032117] Published Tue Sep 30, 2014

]]>Using the high-resolution spectroscopic method of collinear laser–ion-beam spectroscopy (CLIBS), the Zeeman effect of singly ionized praseodymium spectral lines has been studied at relatively small magnetic fields up to 330 G. With this unusual method for studying the Zeeman effect of ionic lines we...

[Phys. Rev. A 90, 032515] Published Tue Sep 30, 2014

]]>We report a high-precision calculation for the hydrogen molecular ion H2+ by using a variational method in Hylleraas coordinates. The calculated nonrelativistic ground-state energy is accurate to 2 parts in 1034, which represents a more than 3 orders of magnitude improvement over the best previous v...

[Phys. Rev. A 90, 032516] Published Tue Sep 30, 2014

]]>Electron elastic scattering off a spin-polarized Cr(...3d54s1, 7S) atom is theoretically studied in the region of electron energies up to 15 eV using both a one-electron “spin-polarized” Hartree-Fock approximation and a multielectron spin-polarized random-phase approximation with exchange. It is fou...

[Phys. Rev. A 90, 032717] Published Tue Sep 30, 2014

]]>Quantum correlations between two neighboring atoms are studied. It is assumed that one atomic system comprises a single auto-ionizing level and the other atom does not contain any auto-ionizing level. The excitation of both atoms is achieved by the interaction with the same mode of the quantized fie...

[Phys. Rev. A 90, 033428] Published Tue Sep 30, 2014

]]>We consider a two-component pancake-shaped, i.e., effectively two-dimensional (2D), Bose-Einstein condensate coupled by the spin-orbit (SO) and Rabi terms. The SO coupling adopted here is of the mixed Rashba-Dresselhaus type. For this configuration, we derive a system of two 2D nonpolynomial Schrödi...

[Phys. Rev. A 90, 033629] Published Tue Sep 30, 2014

]]>We discuss the possibility of realizing a non-Hermitian, i.e., an open two-well system of ultracold atoms by enclosing it within additional time-dependent wells that serve as particle reservoirs. With the appropriate design of the additional wells, PT-symmetric currents can be induced to and from th...

[Phys. Rev. A 90, 033630] Published Tue Sep 30, 2014

]]>We exploit geometric properties of quantum states of light in optical cavities to carry out quantum nondemolition measurements. We generalize the “mode-invisibility” method to obtain information about the Wigner function of a squeezed coherent state in a nondestructive way. We also simplify the appl...

[Phys. Rev. A 90, 033847] Published Tue Sep 30, 2014

]]>Enhanced ionization (EI) of molecules has been extensively studied over the past two decades as a common process in molecular dissociative ionization in strong laser fields. Direct evidence for EI has been found only in I2 and H2. However, in this work we perform a direct study of EI in CO and N2, a...

[Phys. Rev. A 90, 031401] Published Mon Sep 29, 2014

]]>We study the two-dimensional weakly repulsive Bose gas at zero temperature in the presence of correlated disorder. Using large-scale simulations, we show that the low-energy Bogoliubov cumulative density of states remains quadratic up to a critical disorder strength, beyond which a power law with di...

[Phys. Rev. A 90, 031603] Published Mon Sep 29, 2014

]]>The generalized Hartmann effect (GHE) predicts a strict inequality between the traversal times across a contiguous and a separated double-barrier system. This is compared to the implications of the time-of-arrival (TOA) operator approach to barrier traversal time [E. A. Galapon, Phys. Rev. Lett. 108...

[Phys. Rev. A 90, 032115] Published Mon Sep 29, 2014

]]>Various widely used approaches for the exchange-correlation energy of Kohn-Sham theory, such as the generalized gradient approximation and hybrid methods, suffer from the one-electron self-interaction error. This error manifests itself in one-electron or two-electron spin-unpolarized systems. We pro...

[Phys. Rev. A 90, 032513] Published Mon Sep 29, 2014

]]>The stability of antiproton-hydrogen compound states (p¯H) is investigated theoretically. The p¯H compound state has decay channels of atomic electron detachment (→e−+p¯p) and hadronic pair (p¯-p) annihilation, and hence it cannot be permanently stable even if the dissociation channel (→p¯+H) is ene...

[Phys. Rev. A 90, 032514] Published Mon Sep 29, 2014

]]>We present detailed analysis of the recently proposed technique of high-order-harmonic generation spectroscopy of correlation-driven electron hole dynamics in atoms and molecules. This novel technique resolves Auger-type processes with attosecond-scale resolution by clocking the decay process with h...

[Phys. Rev. A 90, 033426] Published Mon Sep 29, 2014

]]>A control strategy incorporating a fixed carrier frequency constraint on the optimal field is presented. As an illustrative example we consider the creation of maximum coherence in a six-level Λ system by solving the Schrödinger equation without the rotating-wave approximation in the field-interacti...

[Phys. Rev. A 90, 033427] Published Mon Sep 29, 2014

]]>We analyze the correlation and spectral properties of two-photon states resonantly transmitted by a nonlinear optical microcavity. We trace the correlation properties of transmitted two-photon states to the decay spectrum of multiphoton resonances in the nonlinear microcavity.

[Phys. Rev. A 90, 033845] Published Mon Sep 29, 2014

]]>In optical interferometry multimode entanglement is often assumed to be the driving force behind quantum enhanced measurements. Recent work has shown this assumption to be false: single-mode quantum states perform just as well as their multimode entangled counterparts. We go beyond this to show that...

[Phys. Rev. A 90, 033846] Published Mon Sep 29, 2014

]]>We have investigated the effect of an external magnetic field on the angular distribution and the linear polarization of the 2s22p53s3P2o→2s22p61S0 emission line in Ne-like ions. Since an electric dipole decay channel is opened by the magnetic field and competes with the inherent magnetic quadrupole...

[Phys. Rev. A 90, 035404] Published Mon Sep 29, 2014

]]>[Phys. Rev. A 90, 039903] Published Mon Sep 29, 2014

]]>In this paper, we treat an asymptotic hypothesis testing (or state discrimination with asymmetric treatment of errors) between an arbitrary fixed bipartite pure state |Ψ〉 and the completely mixed state by one-way local operation and classical communication (LOCC), two-way LOCC, and separable positiv...

[Phys. Rev. A 90, 032327] Published Fri Sep 26, 2014

]]>We study in theory and experiment the verification of the Schmidt number of quantum correlated radiation fields. This measure of entanglement counts the number of global superpositions of product states which are needed to describe a compound quantum system. For unraveling a certain value of this me...

[Phys. Rev. A 90, 032328] Published Fri Sep 26, 2014

]]>High-fidelity controlled-phase gates based on the Rydberg blockade have been studied and their robustness with respect to noise and experimental inaccuracies in pulse timings and amplitudes using both analytic and numerically optimized pulses have been investigated.

[Phys. Rev. A 90, 032329] Published Fri Sep 26, 2014

]]>We present an ab initio three-dimensional precision calculation and analysis of high-order-harmonic generation (HHG) of the hydrogen molecular ion subject to intense elliptically polarized laser pulses by means of the time-dependent generalized pseudospectral method in two-center prolate spheroidal ...

[Phys. Rev. A 90, 033425] Published Fri Sep 26, 2014

]]>[Phys. Rev. A 90, 039902] Published Fri Sep 26, 2014

]]>Two implementations of an error-correction algorithm for topological quantum codes are described, and shown to be promising for fighting decoherence and making quantum computing scalable.

[Phys. Rev. A 90, 032326] Published Thu Sep 25, 2014

]]>Excitation energies, term designations, and g factors of Th, Th+, and Th2+ are determined using a relativistic hybrid configuration-interaction (CI) plus all-order approach that combines configuration-interaction and linearized coupled-cluster methods. The results are compared with other theoretical...

[Phys. Rev. A 90, 032512] Published Thu Sep 25, 2014

]]>We present experimentally measured and theoretically calculated rate coefficients for the electron-ion recombination of W18+([Kr]4d104f10) forming W17+. At low electron-ion collision energies, the merged-beam rate coefficient is dominated by strong, mutually overlapping recombination resonances. In ...

[Phys. Rev. A 90, 032715] Published Thu Sep 25, 2014

]]>We consider the possibilities for producing ultracold mixtures of K and Cs and forming KCs molecules by magnetoassociation. We carry out coupled-channel calculations of the interspecies scattering length for KCs39, KCs41, and KCs40 and characterize Feshbach resonances due to s-wave and d-wave bound ...

[Phys. Rev. A 90, 032716] Published Thu Sep 25, 2014

]]>In a recent Letter [H. Bachau, M. Dondera, and V. Florescu, Phys. Rev. Lett. 112, 073001 (2014)PRLTAO10.1103/PhysRevLett.112.073001] we considered the hydrogen atom in interaction with an electromagnetic field consisting in the coherent superposition of two keV pulses centered around two frequencies...

[Phys. Rev. A 90, 033423] Published Thu Sep 25, 2014

]]>A new method to probe the dynamics of excited states using quantum beats between lower-lying hyperfine states is presented, which is particularly advantageous in room-temperature vapors where ‘traditional’ methods based on continuous excitation fail.

[Phys. Rev. A 90, 033424] Published Thu Sep 25, 2014

]]>We study optimal quantum control of the dynamics of trapped Bose-Einstein condensates: The targets are to split a condensate, residing initially in a single well, into a double well, without inducing excitation, and to excite a condensate from the ground state to the first-excited state of a single ...

[Phys. Rev. A 90, 033628] Published Thu Sep 25, 2014

]]>We report on switching the intensity correlation or anticorrelation by changing the polarization basis for measuring light that has already propagated through the electromagnetically induced transparency (EIT) medium of the 5S1/2(F=2)−5P1/2(F′=1) transition of Rb87 atoms. When a linearly polarized l...

[Phys. Rev. A 90, 033843] Published Thu Sep 25, 2014

]]>A detailed analysis of the propagation of laser Gaussian beams at critical angles shows under which conditions it is possible to maximize the breaking of symmetry in the angular distribution and for which values of the laser wavelength and beam waist it is possible to find an analytic formula for th...

[Phys. Rev. A 90, 033844] Published Thu Sep 25, 2014

]]>Quantum systems are invariably open, evolving under surrounding influences rather than in isolation. Standard open quantum system methods eliminate all information on the environmental state to yield a tractable description of the system dynamics. By incorporating a collective coordinate of the envi...

[Phys. Rev. A 90, 032114] Published Wed Sep 24, 2014

]]>Cluster states with higher-dimensional lattices that cannot be physically embedded in three-dimensional space have important theoretical interest in quantum computation and quantum simulation of topologically ordered condensed-matter systems. We present a simple, scalable, top-down method of entangl...

[Phys. Rev. A 90, 032325] Published Wed Sep 24, 2014

]]>We propose a scheme to bring reduced-density-matrix-functional theory into the realm of density functional theory (DFT) that preserves the accurate density functional description at equilibrium, while incorporating accurately static and left-right correlation effects in molecules and keeping the goo...

[Phys. Rev. A 90, 032511] Published Wed Sep 24, 2014

]]>We demonstrate the nondestructive imaging of a lattice gas of ultracold bosons. Atomic fluorescence is induced in the simultaneous presence of degenerate Raman sideband cooling. The combined influence of these processes controllably cycles an atom between a dark state and a fluorescing state while e...

[Phys. Rev. A 90, 033422] Published Wed Sep 24, 2014

]]>Topological superfluids are recently discovered quantum matter that hosts topologically protected gapless edge states known as Majorana fermions—exotic quantum particles that act as their own antiparticles and obey non-Abelian statistics. Their realizations are believed to lie at the heart of future...

[Phys. Rev. A 90, 033624] Published Wed Sep 24, 2014

]]>We consider an equilibrium single-species homogeneous Bose gas from which a proportion of the atoms are instantaneously and coherently transferred to a second species, thereby forming a binary Bose gas in a non-equilibrium initial state. We study the ensuing evolution towards a new equilibrium, mapp...

[Phys. Rev. A 90, 033625] Published Wed Sep 24, 2014

]]>The contact interaction is often used in modeling ultracold atomic gases, although it leads to pathological behavior arising from the divergence of the many-body wave function when two particles coalesce. This makes it difficult to use this model interaction in quantum Monte Carlo and other popular ...

[Phys. Rev. A 90, 033626] Published Wed Sep 24, 2014

]]>We propose to go beyond the usual Hubbard model description of atoms in optical lattices and show how few-body physics can be used to simulate many-body phenomena, e.g., an electron-phonon system. We take one atomic species to be trapped in a deep optical lattice at full-filling and another to be un...

[Phys. Rev. A 90, 033627] Published Wed Sep 24, 2014

]]>In this paper we present a protocol to engineer interactions confined to subspaces of the Fock space in trapped ions: we show how to engineer upper-bounded, lower-bounded, and sliced Jaynes-Cummings (JC) and anti-Jaynes-Cummings (AJC) Hamiltonians. The upper-bounded (lower-bounded) interaction actin...

[Phys. Rev. A 90, 033840] Published Wed Sep 24, 2014

]]>Linear and nonlinear (especially coherent) electromagnetic interactions of moving many-electron atoms are investigated using a reduced-density-matrix description, which is applied to electromagnetically induced transparency and related resonant pump-probe optical phenomena. External magnetic fields ...

[Phys. Rev. A 90, 033841] Published Wed Sep 24, 2014

]]>We report on the observation of terahertz radiation in a noncentrosymmetric insulating oxide, paratellurite (α-TeO2), by irradiation of a femtosecond laser pulse at room temperature. In the power spectrum of the terahertz radiation, an intensity fringe pattern with a period of ∼0.25 THz shows up bel...

[Phys. Rev. A 90, 033842] Published Wed Sep 24, 2014

]]>In nonrelativistic quantum mechanics, Hudson's theorem states that a Gaussian wave function is the only pure state corresponding to a positive Wigner function (WF). We explicitly construct non-Gaussian Dirac spinors with positive relativistic WFs. These pure relativistic states are coherent superpos...

[Phys. Rev. A 90, 034102] Published Wed Sep 24, 2014

]]>We study quantum tomography based on a stochastic continuous-time measurement record obtained from a probe field collectively interacting with an ensemble of identically prepared systems. In comparison to previous studies, we consider here the case in which the measurement-induced backaction has a n...

[Phys. Rev. A 90, 032113] Published Tue Sep 23, 2014

]]>We show how to extract the scaling behavior of quantum walks using the renormalization group (RG). We introduce the method by efficiently reproducing well-known results on the one-dimensional lattice. For a nontrivial model, we apply this method to the dual Sierpinski gasket and obtain its exact, cl...

[Phys. Rev. A 90, 032324] Published Tue Sep 23, 2014

]]>Tunneling ionization of atoms and molecules plays a major role in strong field physics. In this paper we study the nuclear version of this phenomenon: tunneling dissociation of H2+ and its isotopes in the interaction with THz pulses. We show strong evidence supporting the concept of tunneling dissoc...

[Phys. Rev. A 90, 033421] Published Tue Sep 23, 2014

]]>A parametric two-photon process, involving stimulated emission of two cascaded photons from a bidoped poled material placed inside an optically pumped cavity, is proposed and assessed within the priming photon scheme. We show that, with a specific level configuration for the two dopants A and B, and...

[Phys. Rev. A 90, 033839] Published Tue Sep 23, 2014

]]>One of the key challenges in quantum information is coherently manipulating the quantum state. However, it is an outstanding question whether control can be realized with low error. Only gates from the Clifford group—containing π, π/2, and Hadamard gates—have been characterized with high accuracy. H...

[Phys. Rev. A 90, 030303] Published Mon Sep 22, 2014

]]>Recently, it has been shown that the momentum distribution of a metallic state of fermionic atoms in a lattice Fermi-Bose mixture exhibits coherent oscillations after a global quench that suppresses tunneling. The oscillation period is determined by the Fermi-Bose interaction strength. Here we show ...

[Phys. Rev. A 90, 031602] Published Mon Sep 22, 2014

]]>A simple result is found for the optimal protocol of drivings for a general two-level Hamiltonian, which transports a given initial state to a given final state in minimal time, under additional conditions on the drivings. If one of the three possible drivings is unconstrained in strength the proble...

[Phys. Rev. A 90, 032110] Published Mon Sep 22, 2014

]]>We investigate the smallest set of requirements for inducing non-Markovian dynamics in a collisional model of open quantum systems. This is done by introducing correlations in the state of the environment and analyzing the divisibility of the quantum maps from consecutive time steps. Our model and r...

[Phys. Rev. A 90, 032111] Published Mon Sep 22, 2014

]]>We formulate a series of nontrivial equalities which are satisfied by all no-signaling correlations, meaning that no faster-than-light communication is allowed with the resource of these correlations. All quantum and classical correlations satisfy these equalities since they are no-signaling. By app...

[Phys. Rev. A 90, 032112] Published Mon Sep 22, 2014

]]>A direct analysis of the task of randomness amplification from Santha-Vazirani sources using the violation of the chained Bell inequality is performed in terms of the convex combination of no-signaling boxes required to simulate quantum violation of the inequality. This analysis is used to find the ...

[Phys. Rev. A 90, 032322] Published Mon Sep 22, 2014

]]>Entanglement distribution with separable states has recently attracted considerable attention. Recent results suggest that quantum discord, a measure for quantum correlations beyond entanglement, is responsible for this counterintuitive phenomenon. In this work we study this question from a differen...

[Phys. Rev. A 90, 032323] Published Mon Sep 22, 2014

]]>Reflection of electromagnetic waves from a periodic grating can be described in terms of a discrete coupled multichannel scattering problem. By modeling the grating as a space- and frequency-dependent dielectric, it is possible to use a variable phase method, applied to a generalized Helmholtz equat...

[Phys. Rev. A 90, 032507] Published Mon Sep 22, 2014

]]>Energies of satellite-free emission lines from hydrogenlike and heliumlike trapped argon ions have been absolutely determined with an accuracy of 4-5 ppm and relative measurements on sulfur ions reached an accuracy around 10 ppm, thereby making these results one of the most precise x-ray transition energies that have been reported so far for highly charged ions.

[Phys. Rev. A 90, 032508] Published Mon Sep 22, 2014

]]>The electric and magnetic dipole radiations due to a double-electron jump from the 1S0 state of He-like ions with an empty K shell are evaluated for 21 ions with 10≤Z≤92 using fully relativistic multiconfiguration Dirac-Fock wave functions in the active space approximation with the inclusion of a fi...

[Phys. Rev. A 90, 032509] Published Mon Sep 22, 2014

]]>The He2-Ne system with the combination of the isotopes of helium (He3 and He4) is used in structure calculations. Three-body channel functions and adiabatic potential functions have been calculated using the B-spline method. We use these channel functions in the slow variable discretization method t...

[Phys. Rev. A 90, 032510] Published Mon Sep 22, 2014

]]>Using the classical ensemble model, we investigate the sensitivity of double ionization in circularly polarized laser fields to the initial ensembles that are generated for an Ar atom with a definite total angular momentum. The numerical results show that the double-ionization probability in the cou...

[Phys. Rev. A 90, 033420] Published Mon Sep 22, 2014

]]>We use the mean-field method, the quantum Monte Carlo method and the density-matrix-renormalization-group method to study the trimer superfluid phase and the quantum phase diagram of the Bose-Hubbard model in a one-dimensional optical lattice, with an explicit trimer-tunneling term. Theoretically, w...

[Phys. Rev. A 90, 033622] Published Mon Sep 22, 2014

]]>We study isolated finite interacting quantum systems after an instantaneous perturbation and show three scenarios in which the probability for finding the initial state later in time (fidelity) decays nonexponentially, often all the way to saturation. The decays analyzed involve Gaussian, Bessel of ...

[Phys. Rev. A 90, 033623] Published Mon Sep 22, 2014

]]>We study light-induced spatial crystallization of ultracold quantum particles confined along the axis of a high-Q linear cavity via a transverse multicolor pump using numerical simulations. Whenever a pump frequency is tuned close to resonance with a longitudinal cavity mode, the dynamics favors bis...

[Phys. Rev. A 90, 033833] Published Mon Sep 22, 2014

]]>Interferometry with massive particles may have the potential to explore the limitations of standard quantum mechanics, in particular where it concerns its boundary with general relativity and the yet to be developed theory of quantum gravity. This development is hindered considerably by the lack of ...

[Phys. Rev. A 90, 033834] Published Mon Sep 22, 2014

]]>Experimental setups for the optical implementation of projective measurements in the Laguerre-Gaussian basis are discussed. Special attention is given to the case where the measurements are made with the aid of single-mode fibers that are used to extract the Gaussian component from an optical distri...

[Phys. Rev. A 90, 033835] Published Mon Sep 22, 2014

]]>We study the operation of linear optics schemes for entanglement distribution based on nonlocal photon subtraction when input states, produced by imperfect single-photon sources, exhibit both vacuum and multiphoton contributions. Two models for realistic photon statistics with radically different pr...

[Phys. Rev. A 90, 033836] Published Mon Sep 22, 2014

]]>We study secondary instabilities in a coherently driven passive optical fiber cavity. We show that time-modulated solutions which are generated at the onset of instability experience convective and absolute Eckhaus instabilities. The splitting of the secondary instabilities into convective and absol...

[Phys. Rev. A 90, 033837] Published Mon Sep 22, 2014

]]>We investigate a hybrid quantum system consisting of a cavity optomechanical device optically coupled to an ultracold quantum gas. We show that the dispersive properties of the ultracold gas can be used to dramatically modify the optomechanical response of the mechanical resonator. We examine hybrid...

[Phys. Rev. A 90, 033838] Published Mon Sep 22, 2014

]]>We identify that both the dynamic core polarization and dynamic orbital deformation are important in the orientation-dependent high-order harmonic generation of CO molecules subjected to intense few cycle laser fields. These polarization dynamics allow for the observation of strong orientation effec...

[Phys. Rev. A 90, 035402] Published Mon Sep 22, 2014

]]>Electron scattering on a nucleus in a field of two unidirectional pulsed laser waves is considered. The parametric interference effect is studied, which manifests in electron scattering within the plane formed by both the direction of laser-wave propagation and the initial electron momentum (the int...

[Phys. Rev. A 90, 035403] Published Mon Sep 22, 2014

]]>A novel scheme for the creation of artificial spin-orbit coupling for neutral ultracold atoms in an optical lattice is proposed, using a combination of fast periodic shaking of the atoms and microwave dressing rather than near-resonant light fields.

[Phys. Rev. A 90, 031601] Published Fri Sep 19, 2014

]]>The physics of one-dimensional optical superlattices with resonant s-p orbitals is reexamined in the language of appropriate Wannier functions. It is shown that details of the tight-binding model realized in different optical potentials crucially depend on the proper determination of Wannier functio...

[Phys. Rev. A 90, 033621] Published Fri Sep 19, 2014

]]>Optical-frequency combs consisting of equally spaced sharp lines in frequency space have triggered substantial advances in optical-frequency metrology and precision measurements and in applications such as laser-based gas sensing and molecular fingerprinting. Here, we propose a scheme to generate a ...

[Phys. Rev. A 90, 033830] Published Fri Sep 19, 2014

]]>An arbitrary initial state of an optical or microwave field in a lossy driven nonlinear cavity can be changed into a partially incoherent superposition of only the vacuum and the single-photon states. This effect is known as single-photon blockade, which is usually analyzed for a Kerr-type nonlinear...

[Phys. Rev. A 90, 033831] Published Fri Sep 19, 2014

]]>We study the photon-photon correlation properties of two-photon transport in a one-dimensional waveguide coupled to a nonlinear cavity via a real-space approach. It is shown that the intrinsic dissipation of the nonlinear cavity has an important effect upon the correlation of the transported photons...

[Phys. Rev. A 90, 033832] Published Fri Sep 19, 2014

]]>[Phys. Rev. A 90, 039901] Published Fri Sep 19, 2014

]]>Identifying weakly coupled nuclear spins around single electron spins is a key step toward implementing quantum information processing using coupled electron-nuclei spin systems or sensing like single-spin nuclear magnetic resonance detection using diamond defect spins. Dynamical decoupling control ...

[Phys. Rev. A 90, 032319] Published Thu Sep 18, 2014

]]>Phase-randomized light is one of the key assumptions in the security proof of the Bennett-Brassard 1984 (BB84) quantum-key-distribution (QKD) protocol using an attenuated laser. Though the assumption has been believed to be satisfied for conventional systems, it should be reexamined for current high...

[Phys. Rev. A 90, 032320] Published Thu Sep 18, 2014

]]>The radiative association processes for Na+ colliding with Rb87(5s) atoms have been investigated by using the quantum-mechanical method. The total and partial cross sections that associate to the specific rovibrational states are calculated rigorously in the energy range of 10−13−1.2×10−2eV. The ass...

[Phys. Rev. A 90, 032714] Published Thu Sep 18, 2014

]]>We propose a theoretical scheme for realizing selective coherent spin transportation in a spin-orbit-coupled bosonic gas trapped in a symmetric double well by fast modulation of the energy-level unbalance between the two wells. The modulation can be tuned in such a way that an arbitrarily, a priori ...

[Phys. Rev. A 90, 033618] Published Thu Sep 18, 2014

]]>We study in three dimensions the problem of a spatially homogeneous zero-temperature ideal Fermi gas of spin-polarized particles of mass m perturbed by the presence of a single distinguishable impurity of mass M. The interaction between the impurity and the fermions involves only the partial s wave ...

[Phys. Rev. A 90, 033619] Published Thu Sep 18, 2014

]]>We demonstrate tomographic reconstruction of the phase space distribution of atoms oscillating in a harmonic trap with weak potential corrugation caused by nanoscale imperfections in an atom chip. We find that deformations in these distributions are highly sensitive to anharmonic components of the p...

[Phys. Rev. A 90, 033620] Published Thu Sep 18, 2014

]]>In the uncertainty budget of primary atomic cesium fountain clocks, evaluations of frequency-pulling shifts of the hyperfine clock transition caused by unintentional excitation of its nearby transitions (Rabi and Ramsey pulling) have been based so far on an approach developed for cesium beam clocks....

[Phys. Rev. A 90, 033829] Published Thu Sep 18, 2014

]]>We investigate the parity- and time-reversal (PT-) symmetry breaking in lattice models in the presence of long-ranged, non-Hermitian, PT-symmetric potentials that remain finite or become divergent in the continuum limit. By scaling analysis of the fragile PT threshold for an open finite lattice, we ...

[Phys. Rev. A 90, 032108] Published Wed Sep 17, 2014

]]>We consider an analytical approach that involves the complex poles of the propagator to investigate the effect due to the lack of time-reversal invariance on the time evolution of decay for purely absorptive potentials. We find that the choice of the initial state may change the exponential decaying...

[Phys. Rev. A 90, 032109] Published Wed Sep 17, 2014

]]>For qubits, Monte Carlo estimation of the average fidelity of Clifford unitaries is efficient: it requires a number of experiments that is independent of the number n of qubits and classical computational resources that scale only polynomially in n. Here, we identify the requirements for efficient M...

[Phys. Rev. A 90, 032317] Published Wed Sep 17, 2014

]]>A bipartite state ρAB is symmetric extendible if there exists a tripartite state ρABB′ whose AB and AB′ marginal states are both identical to ρAB. Symmetric extendibility of bipartite states is of vital importance in quantum information because of its central role in separability tests, one-way dist...

[Phys. Rev. A 90, 032318] Published Wed Sep 17, 2014

]]>Cryogenic buffer-gas beams are a promising method for producing bright sources of cold molecular radicals for cold-collision and chemical-reaction experiments. In order to use these beams in studies of reactions with controlled collision energies or in trapping experiments, one needs a method of con...

[Phys. Rev. A 90, 033418] Published Wed Sep 17, 2014

]]>Recently, violation of the Cauchy-Schwarz inequality by the second-order correlation function was reported in a collection of ultracold bosons [Kheruntsyan et al., Phys. Rev. Lett. 108, 260401 (2012)PRLTAO10.1103/PhysRevLett.108.260401]. We show that the observation of this effect proves the presenc...

[Phys. Rev. A 90, 033616] Published Wed Sep 17, 2014

]]>We present a general scheme to realize a cold-atom quantum simulator of bidimensional atomic crystals. Our model is based on the use of two independently trapped atomic species: the first one, subject to a strong in-plane confinement, constitutes a two-dimensional matter wave which interacts only wi...

[Phys. Rev. A 90, 033617] Published Wed Sep 17, 2014

]]>The balances of the electromagnetic powers and momentum flows for the system of a dielectric particle and a dielectric slab waveguide are studied. The emphasis is made on the regime when whispering gallery resonances in the particle are excited. The excitation is achieved by a guided mode that has e...

[Phys. Rev. A 90, 033825] Published Wed Sep 17, 2014

]]>High spectral mode density of conventional optical cavities is detrimental to the generation of broad optical frequency combs and to other linear and nonlinear applications. In this work we optimize the morphology of high-Q whispering gallery (WG) and Fabry-Perot (FP) cavities and find a set of para...

[Phys. Rev. A 90, 033826] Published Wed Sep 17, 2014

]]>