We propose a procedure for tomographic characterization of continuous-variable quantum operations which employs homodyne detection and single-mode squeezed probe states with a fixed degree of squeezing and antisqueezing and a variable displacement and orientation of squeezing ellipse. Density matrix…

[Phys. Rev. A 92, 022101] Published Mon Aug 03, 2015

]]>A long-standing challenge in the foundations of quantum mechanics is the verification of alternative collapse theories despite their mathematical similarity to decoherence. To this end, we suggest a method based on dynamical decoupling. Experimental observation of nonzero saturation of the decouplin…

[Phys. Rev. A 92, 022102] Published Mon Aug 03, 2015

]]>We give a theoretical study of a double-cavity system in which a mechanical resonator beam is coupled to two cavity modes on both sides through radiation pressures. The indirect coupling between the cavities via the resonator sets up a correlation in the optomechanical entanglements between the two …

[Phys. Rev. A 92, 022301] Published Mon Aug 03, 2015

]]>Knowing the dimension of an unknown physical system has practical relevance, as dimensionality plays an important role in various information theoretic tasks. In this work we show that a modified version of Hardy's argument, which reveals the contradiction of quantum theory with *local realism*, turns…

[Phys. Rev. A 92, 022302] Published Mon Aug 03, 2015

]]>Tight-binding lattices offer a unique platform in which particles may be either static or mobile depending on the potential barrier between the sites. How to harness this mobility in a many-site lattice for useful operations is still an open question. We show how effective linear opticslike operatio…

[Phys. Rev. A 92, 022701] Published Mon Aug 03, 2015

]]>Absolute cross sections for the single and double *K*-shell photoionization of carbonlike ${\mathrm{O}}^{2+}$ and nitrogenlike ${\mathrm{O}}^{+}$ ions were measured in the 526–620-eV photon energy range by employing the ion-photon merged-beam technique at the SOLEIL synchrotron radiation facility. High-resolution spectroscopy up to $\dots $

[Phys. Rev. A 92, 023401] Published Mon Aug 03, 2015

]]>We present a joint experimental and theoretical study of ionization of argon atoms by a linearly polarized two-color laser field (${\lambda}_{1}=800$ nm, ${\lambda}_{2}=400$ nm). Changing the relative phase $\phi $ between the two colors, the forward-backward asymmetry of the doubly differential momentum distribution of emitted el…

[Phys. Rev. A 92, 023402] Published Mon Aug 03, 2015

]]>We use the functional renormalization group to study the spectrum of three- and four-body states in bosonic systems around the unitary limit. Our effective action includes all energy-independent contact interactions in the four-atom sector, and we introduce a running trimer field to eliminate coupli…

[Phys. Rev. A 92, 023601] Published Mon Aug 03, 2015

]]>We study ultracold atoms in an optical lattice with two local minima per unit cell and show that the low-energy states of a multiband Bose-Hubbard (BH) Hamiltonian with only pairwise interactions are equivalent to an effective single-band Hamiltonian with strong three-body interactions. We focus on …

[Phys. Rev. A 92, 023602] Published Mon Aug 03, 2015

]]>We demonstrate experimentally an alternative method for the dynamic generation of atomic spin squeezing, building on the interplay between linear coupling and nonlinear phase evolution. Since the resulting quantum dynamics can be seen as rotation and shear on the generalized Bloch sphere, we call th…

[Phys. Rev. A 92, 023603] Published Mon Aug 03, 2015

]]>Gamow vectors are used to study nonlinear wave dynamics, and it is found that the quantization of the decay rates described by these vectors successfully explains the irreversibility of dispersive shock waves.

[Phys. Rev. A 92, 023801] Published Mon Aug 03, 2015

]]>Stretched cavity soliton (SCS) in dispersion-managed nonlinear resonators is numerically investigated. SCS is found to stretch and compress twice during a round-trip propagation inside the dispersion-managed resonator, exhibiting a pulse dynamics similar to dispersion-managed mode-locked femtosecond…

[Phys. Rev. A 92, 023802] Published Mon Aug 03, 2015

]]>The dynamics of optical pulses in noninstantaneous Kerr media are considered. It is found that the “mass center” of the localized profile exhibits an accelerated transversal (on the time axis) motion during propagation. In the highly noninstantaneous regime, especially, the motion can approximately …

[Phys. Rev. A 92, 023803] Published Mon Aug 03, 2015

]]>We study the problem of estimating the magnitude of a Gaussian beam displacement using a two-pixel or “split” detector. We calculate the maximum likelihood estimator and compute its asymptotic mean-squared error via the Fisher information. Although the signal-to-noise ratio is known to be simply rel…

[Phys. Rev. A 92, 012130] Published Fri Jul 31, 2015

]]>Topological quantum computing promises error-resistant quantum computation without active error correction. However, there is a worry that during the process of executing quantum gates by braiding anyons around each other, extra anyonic excitations will be created that will disorder the encoded quan…

[Phys. Rev. A 92, 012336] Published Fri Jul 31, 2015

]]>We show that deterministic quantum computing with one qubit (DQC1) can be experimentally implemented with a spatial light modulator, using the polarization and the transverse spatial degrees of freedom of light. The scheme allows the computation of the trace of a high-dimension matrix, being limited…

[Phys. Rev. A 92, 012337] Published Fri Jul 31, 2015

]]>We investigate how the efficiency of the quantum teleportation protocol is affected when the qubits involved in the protocol are subjected to noise or decoherence. We study all types of noise usually encountered in real-world implementations of quantum communication protocols, namely, the bit-flip, …

[Phys. Rev. A 92, 012338] Published Fri Jul 31, 2015

]]>We have investigated resonant Auger decay of xenon following photoexcitation of each of the three $L$ edges under resonant-Raman conditions, which allowed us to characterize several higher Rydberg transitions. Relative intensities for spectator final states reached after ${L}_{1}\text{\u2212}$, ${L}_{2}\text{\u2212}$, and ${L}_{3}$-edge excitati…

[Phys. Rev. A 92, 013427] Published Fri Jul 31, 2015

]]>Synthetic spin-orbit (SO) coupling, an important ingredient for quantum simulation of many exotic condensed matter physics, has recently attracted considerable attention. The static and dynamic properties of a SO-coupled Bose-Einstein condensate (BEC) have been extensively studied in both theory and…

[Phys. Rev. A 92, 013635] Published Fri Jul 31, 2015

]]>We study the process of scattering of two-dimensional dark solitons, and their vortex-antivortex pairs as a specific case, by a single quantum vortex in a Bose-Einstein condensate with repulsive interaction between atoms. An asymptotic theory describing the dynamics of such solitonlike structures in…

[Phys. Rev. A 92, 013636] Published Fri Jul 31, 2015

]]>The effect of dipolar orientation with respect to the soliton plane on the physics of two-dimensional bright solitons in dipolar Bose-Einstein condensates is discussed. Previous studies on such a soliton involved dipoles either perpendicular or parallel to the condensate plane. The tilting angle con…

[Phys. Rev. A 92, 013637] Published Fri Jul 31, 2015

]]>We apply the global thermodynamic variables approach to experimentally determine the isothermal compressibility parameter ${\kappa}_{T}$ of a trapped Bose gas across the phase transition. We demonstrate the behavior of ${\kappa}_{T}$ around the critical pressure, revealing the second-order nature of the phase transition. C…

[Phys. Rev. A 92, 013638] Published Fri Jul 31, 2015

]]>We analyze the energetic and dynamical properties of bright-bright (BB) soliton pairs in a binary mixture of Bose-Einstein condensates subjected to the action of a combined optical lattice, acting as an external potential for the first species while modulating the intraspecies coupling constant of t…

[Phys. Rev. A 92, 013639] Published Fri Jul 31, 2015

]]>We theoretically investigate interactions between nondegenerate mechanical oscillators mediated by a time-dependent cavity field. We obtain a reduced master equation valid for all optomechanical systems operating in the weak-coupling regime. This master equation includes all forms of decoherence and…

[Phys. Rev. A 92, 013851] Published Fri Jul 31, 2015

]]>We propose to realize mechanical parity-time $\left(\mathcal{PT}\right)$ symmetry in two coupled optomechanical systems. To provide gain to one mechanical resonator and the same amount of damping to the other, the two optical cavities should be driven by blue- and red-detuned laser fields, respectively. After adiabaticall…

[Phys. Rev. A 92, 013852] Published Fri Jul 31, 2015

]]>In this Comment, we show that the author's conclusion in Phys. Rev. A **85**, 023807 (2012) that “the momentum transferred to a submerged mirror upon reflection of a single photon of frequency ${\omega}_{0}$ could be anywhere in the range from $2\hslash {\omega}_{0}/nc$ to $2n\hslash {\omega}_{0}/c$, depending on the phase angle $\psi $ of the mirror's refle…

[Phys. Rev. A 92, 017803] Published Fri Jul 31, 2015

]]>[Phys. Rev. A 92, 017804] Published Fri Jul 31, 2015

]]>We propose a methodology to design Wigner representations in phase spaces with nontrivial topology having evolution equations with desired mathematical properties. As an illustration, two representations of molecular rotations are developed to facilitate the analysis of molecular alignment in modera…

[Phys. Rev. A 92, 012129] Published Thu Jul 30, 2015

]]>We propose to experimentally explore the Haldane phase in spin-one *XXZ* antiferromagnetic chains using trapped ions. We show how to adiabatically prepare the ground states of the Haldane phase, demonstrate their robustness against sources of experimental noise, and propose ways to detect the Haldane …

[Phys. Rev. A 92, 012334] Published Thu Jul 30, 2015

]]>Entanglement distribution is key to the success of secure communication schemes based on quantum mechanics, and there is a strong need for an ultimate architecture able to overcome the limitations of recent proposals such as those based on entanglement percolation or quantum repeaters. In this work …

[Phys. Rev. A 92, 012335] Published Thu Jul 30, 2015

]]>By combining electronic structure and scattering calculations, quasidiabatic potential energy surfaces of both bound Rydberg and electronic resonant states of the water molecule are calculated at the multireference configuration-interaction level. The scattering matrix calculated at low collision en…

[Phys. Rev. A 92, 012708] Published Thu Jul 30, 2015

]]>We investigate the intrinsic-to-extrinsic supersolid (SS) transition in a lattice ultracold Bose gas with strong long-range interaction. When changing the depth of the periodic lattice potential, the transition is shown to manifest in the ground-state wave function and energy, the change of superflu…

[Phys. Rev. A 92, 013634] Published Thu Jul 30, 2015

]]>We propose a method to calculate the operator entanglement and entangling power of a noisy nonunitary operation in terms of linear entropy. By decomposing the Kraus operators of noisy evolution as the sum of products of Pauli matrices, we derive the analytical expression of the operator entanglement…

[Phys. Rev. A 92, 012127] Published Wed Jul 29, 2015

]]>Dephasing and decay are the intrinsic dissipative processes prevalent in any open quantum system and the dominant mechanisms for the loss of coherence and entanglement. This inadvertent effect not only can be overcome but can even be capitalized on in a dissipative quantum simulation by means of tai…

[Phys. Rev. A 92, 012128] Published Wed Jul 29, 2015

]]>We consider the expected violations of Bell inequalities from random pure states. More precisely, we focus on a slightly generalized version of the Collins-Gisin-Linden-Massar-Popescu inequality, which concerns Bell experiments of two parties, two measurement options, and $N$ outcomes, and analyze the…

[Phys. Rev. A 92, 012331] Published Wed Jul 29, 2015

]]>In this paper, we mainly study the local indistinguishability of mutually orthogonal product basis quantum states in $d\otimes d$. In $3\otimes 3$, Bennett *et al.* [ Phys. Rev. A **59**, 1070 (1999)] presented nine orthogonal product basis quantum states which cannot be distinguished by local operations and classical comm…

[Phys. Rev. A 92, 012332] Published Wed Jul 29, 2015

]]>Measurement-device-independent quantum key distribution (MDI-QKD) can provide enhanced security compared to traditional QKD, and it constitutes an important framework for a quantum network with an untrusted network server. Still, a key assumption in MDI-QKD is that the sources are trusted. We propos…

[Phys. Rev. A 92, 012333] Published Wed Jul 29, 2015

]]>We present an extension of the resolvent operator method to extract fully differential ionization probabilities resulting from the interaction of ultrashort laser pulses with ${\text{H}}_{2}{}^{+}$ by including all electronic and vibrational (dissociative) degrees of freedom. The wave function from which ionization pr…

[Phys. Rev. A 92, 013426] Published Wed Jul 29, 2015

]]>[Phys. Rev. A 92, 019903] Published Wed Jul 29, 2015

]]>[Phys. Rev. A 92, 019904] Published Wed Jul 29, 2015

]]>We address the use of entangled qubits as quantum probes to characterize the noise induced by complex environments. In particular, we show that a joint measurement on entangled probes can improve estimation of the correlation time for a broad class of environmental noises compared to sequential stra…

[Phys. Rev. A 92, 010302(R)] Published Tue Jul 28, 2015

]]>Here we propose a route to the high-$Q$ perfect absorption of light by introducing the concept of a Fano antilaser. Based on the drastic spectral variation of the optical phase in a Fano-resonant system, a spectral singularity for scatter-free perfect absorption can be achieved with an order of magnit…

[Phys. Rev. A 92, 011802(R)] Published Tue Jul 28, 2015

]]>A proposed interferometry experiment could test quantum gravity theories by entangling two mirrors weighing as much as apples.

[Phys. Rev. A 92, 012126] Published Tue Jul 28, 2015

]]>We present a scheme to generate an all-range long repulsive Casimir-Polder potential between a perfect negative reflecting surface and a ground-state atom. The repulsive potential is stable and does not decay with time. The Casimir-Polder potential is proportional to ${z}^{-2}$ at short atom-surface distan…

[Phys. Rev. A 92, 012522] Published Tue Jul 28, 2015

]]>In a gas of ultracold atoms whose scattering length is controlled by a magnetic Feshbach resonance, atoms can be associated into universal dimers by an oscillating longitudinal magnetic field. In addition to the harmonic resonance with frequency near that determined by the dimer binding energy, ther…

[Phys. Rev. A 92, 013425] Published Tue Jul 28, 2015

]]>A method to measure the temperature of a cold atomic cloud is developed by relating atoms’ motion to fluorescence photons emitted into an optical nanofiber, where the temperature readout from the temporal correlations of the photons agrees well with standard time-of-flight measurements.

[Phys. Rev. A 92, 013850] Published Tue Jul 28, 2015

]]>We report a time-resolved study of the thermalization dynamics and the lasing to photon Bose-Einstein condensation crossover by *in situ* monitoring the photon kinetics in a dye microcavity. When the equilibration of the light to the dye temperature by absorption and reemission is faster than photon l…

[Phys. Rev. A 92, 011602(R)] Published Mon Jul 27, 2015

]]>Postselected weak measurement has aroused broad interest for its distinctive ability to amplify small physical quantities. However, the low postselection efficiency to obtain a large weak value has been a big obstacle to its application in practice since it may waste resources, and reduce the measur…

[Phys. Rev. A 92, 012120] Published Mon Jul 27, 2015

]]>We consider a simple quantum model of atom-molecule conversion where bosonic atoms can combine into diatomic molecules and vice versa. The many-particle system can be expressed in terms of the generators of a deformed $\text{su}\left(2\right)$ algebra, and the mean-field dynamics takes place on a deformed version of th…

[Phys. Rev. A 92, 012121] Published Mon Jul 27, 2015

]]>In a recent paper [Phys. Rev. A **90**, 043830 (2014)] it was shown that the so-called aperture response tensor is the central concept in the microscopic quantum theory of light diffraction from a small hole in a flat screen. It was further shown that the quantum mechanical theory of diffraction only re…

[Phys. Rev. A 92, 012122] Published Mon Jul 27, 2015

]]>The proton radius puzzle questions the self-consistency of theory and experiment in light muonic and electronic bound systems. Here we summarize the current status of virtual particle models as well as Lorentz-violating models that have been proposed in order to explain the discrepancy. Highly charg…

[Phys. Rev. A 92, 012123] Published Mon Jul 27, 2015

]]>An ever broader range of physical platforms provides the possibility to study and engineer quantum dynamics under continuous measurements. In many experimental arrangements the system of interest is monitored by means of an ancillary device, whose sole purpose is to transduce the signal from the sys…

[Phys. Rev. A 92, 012124] Published Mon Jul 27, 2015

]]>Noise is often regarded as anathema to quantum computation, but in some settings it can be an unlikely ally. We consider the problem of learning the class of $n$-bit parity functions by making queries to a quantum example oracle. In the absence of noise, quantum and classical parity learning are easy …

[Phys. Rev. A 92, 012327] Published Mon Jul 27, 2015

]]>Quantum theory imposes fundamental limitations on the amount of information that can be carried by any quantum system. On the one hand, the Holevo bound rules out the possibility of encoding more information in a quantum system than in its classical counterpart, comprised of perfectly distinguishabl…

[Phys. Rev. A 92, 012328] Published Mon Jul 27, 2015

]]>We report entanglement swapping with time-bin entangled photon pairs, each constituted of a 795-nm photon and a 1533-nm photon, that are created via spontaneous parametric down conversion in a nonlinear crystal. After projecting the two 1533-nm photons onto a Bell state, entanglement between the two…

[Phys. Rev. A 92, 012329] Published Mon Jul 27, 2015

]]>Analog quantum simulators can be used to study quantum correlation in novel many-body systems by emulating the Hamiltonian of these systems. One essential question in quantum simulation is to probe the properties of an emulated many-body system. Here we present a circuit QED scheme for probing such …

[Phys. Rev. A 92, 012330] Published Mon Jul 27, 2015

]]>There are different predictions regarding the position of the isomeric state of ${}^{229m}\mathrm{Th}$. There is some question as to whether it even exists. We propose simple experiments to provide the evidence of the existence of this isomeric state. If the metastable isomeric state exists, we should be able to ob…

[Phys. Rev. A 92, 012519] Published Mon Jul 27, 2015

]]>By explicit construction of counterexamples having the same eigenvalue spectrum of one-matrix, but different two-matrix, we show that density-matrix functionals for the electronic energy that are based solely on the eigenvalues of the one-matrix cannot be unique in functional representation of the t…

[Phys. Rev. A 92, 012520] Published Mon Jul 27, 2015

]]>It is demonstrated that the TaN molecule is the best candidate to search for a *T,P*-violating nuclear magnetic quadrupole moment (MQM), and it looks promising for the search for other *T,P*-odd effects. We report results of coupled-cluster calculations of *T,P*-odd effects in TaN produced by the Ta nucle…

[Phys. Rev. A 92, 012521] Published Mon Jul 27, 2015

]]>By analyzing measured infrared absorption of pure $\mathrm{C}{\mathrm{H}}_{4}$ gas under both “free” (large sample cell) and “confined” (inside the pores of a silica xerogel sample) conditions we give a demonstration that molecule-molecule and molecule-surface collisions lead to very different propensity rules for rotationa…

[Phys. Rev. A 92, 012707] Published Mon Jul 27, 2015

]]>Using the reconstruction of attosecond beating by interference of two-photon transitions (RABBITT) technique, a nonzero phase difference is observed in the two-photon ionization transition of krypton atoms into the ionization channels ${}^{2}P_{1/2}$ and ${}^{2}P_{3/2}$ when an electron is removed from the $4p$ shell. Th…

[Phys. Rev. A 92, 013424] Published Mon Jul 27, 2015

]]>Spin-exchange interaction between atoms in a spin-1 Bose-Einstein condensate causes atomic spin evolving periodically under the single-spatial-mode approximation in the mean-field theory. By applying fast magnetic pulses according to a two-step or a four-step control protocol, we find analytically t…

[Phys. Rev. A 92, 013630] Published Mon Jul 27, 2015

]]>Using the lattice Monte Carlo method, we compute the energy and Tan's contact in the ground state as well as the first excited state of few- to many-fermion systems in a one-dimensional periodic box. We focus on unpolarized systems of $N=4,6,...,12$ particles, with a zero-range interaction, and a wide…

[Phys. Rev. A 92, 013631] Published Mon Jul 27, 2015

]]>We propose a scheme to simulate and explore Weyl semimetal physics with ultracold fermionic atoms in a two-dimensional square optical lattice subjected to experimentally realizable spin-orbit coupling and an artificial dimension from an external parameter space, which may increase experimental feasi…

[Phys. Rev. A 92, 013632] Published Mon Jul 27, 2015

]]>We study a two-dimensional spin-orbit-coupled dipolar Bose-Einstein condensate with repulsive contact interactions by both the variational method and the imaginary-time evolution of the Gross-Pitaevskii equation. The dipoles are completely polarized along one direction in the two-dimensional plane t…

[Phys. Rev. A 92, 013633] Published Mon Jul 27, 2015

]]>We study the resonant properties of photonic crystal slabs theoretically. An $\omega -{k}_{x}$ Fano line shape that approximates the transmission (reflection) spectrum is obtained. This approximation, being a function of light's frequency and in-plane wave vector, generalizes the conventional Fano line shape. Tw…

[Phys. Rev. A 92, 013845] Published Mon Jul 27, 2015

]]>Bare-state population inversion is demonstrated in a two-level system with all dipole matrix elements nonzero. A laser field is resonantly driving the sample, whereas a second weaker and lower frequency coherent field additionally pumps it near resonance with the dynamically Stark-splitted states. D…

[Phys. Rev. A 92, 013846] Published Mon Jul 27, 2015

]]>We investigate the range of validity of the recently developed steady-state *ab initio* laser theory (SALT). While very efficient in describing various microlasers, SALT is conventionally believed not to be applicable to lasers featuring fully or nearly degenerate pairs of resonator modes above the la…

[Phys. Rev. A 92, 013847] Published Mon Jul 27, 2015

]]>Synchronous-asynchronous mode-locking transition in a hybrid active and passive mode-locked laser is investigated theoretically. Three distinct mode-locking states are found and their transition diagram under varying detuning frequency and modulation strength is determined. By examining the steady-s…

[Phys. Rev. A 92, 013848] Published Mon Jul 27, 2015

]]>A lot of experimental and theoretical studies of a system in cavity quantum electrodynamics (cavity QED), which consists of two spatially separated quantum emitters strongly coupled to a single optical cavity mode, have recently attracted much interest in the quantum optics community for various qua…

[Phys. Rev. A 92, 013849] Published Mon Jul 27, 2015

]]>The dynamic dipole polarizabilities for the four lowest triplet states ($2{\phantom{\rule{0.16em}{0ex}}}^{3}S,3{\phantom{\rule{0.16em}{0ex}}}^{3}S,2{\phantom{\rule{0.16em}{0ex}}}^{3}P$, and $3{\phantom{\rule{0.16em}{0ex}}}^{3}P$) of helium are calculated using the $B$-spline configuration interaction method. Present values of the static dipole polarizabilities in the length, velocity, and acceleration gauges are in good agreement wi…

[Phys. Rev. A 92, 012515] Published Fri Jul 24, 2015

]]>In this paper, we propose an in-depth review of the vector and tensor polarizabilities of the two energy levels of the ${}^{87}\mathrm{Sr}$ clock transition whose measurement was reported in P. G. Westergaard *et al.* [Phys. Rev. Lett. **106**, 210801 (2011)]. We conduct a theoretical calculation that reproduces the meas…

[Phys. Rev. A 92, 012516] Published Fri Jul 24, 2015

]]>We have developed an all-optical method for measuring the lifetimes of $nS$ and $nD$ Rydberg states and demonstrate its capabilities with measurements on a dilute cloud of ultracold ${}^{87}\mathrm{Rb}$ atoms in a cryogenic environment. The method is based on the time-resolved observation of resonant light absorption b…

[Phys. Rev. A 92, 012517] Published Fri Jul 24, 2015

]]>Gross-Oliveira-Kohn density-functional theory (GOK-DFT) for ensembles is, in principle, very attractive but has been hard to use in practice. A practical model based on GOK-DFT for the calculation of electronic excitation energies is discussed. The model relies on two modifications of GOK-DFT: use o…

[Phys. Rev. A 92, 012518] Published Fri Jul 24, 2015

]]>Two-color ionization of atoms with a strong 800-nm fundamental component and a weak 400-nm component with perpendicular polarization gives detailed insight into the ionization dynamics. When the delay between the two colors is varied on a subcycle scale, the slow-electron signal shows an oscillatory…

[Phys. Rev. A 92, 013422] Published Fri Jul 24, 2015

]]>The differential cross section for electron-impact excitation of helium atoms in the presence of a linearly polarized laser field is calculated. The interaction of the laser field with both the projectile electron and the target atom is treated in a fully nonperturbative way, while the electron-atom…

[Phys. Rev. A 92, 013423] Published Fri Jul 24, 2015

]]>We propose a scheme for preparing an ensemble of atoms in a maximally entangled $W$ state by exploiting the Rydberg blockade effect. The success of our protocol is indicated by the detection of an ion, which thus serves as a herald for successful entangled-state preparation. The fidelity of the prepar…

[Phys. Rev. A 92, 013629] Published Fri Jul 24, 2015

]]>The change in the decay rate of an excited atom that is brought about by extinction and thermal-radiation effects in a nearby dielectric medium is determined from a quantum-mechanical model. The medium is a collection of randomly distributed thermally excited spherical scatterers with absorptive pro…

[Phys. Rev. A 92, 013843] Published Fri Jul 24, 2015

]]>We undertake a thorough analysis of the thermodynamics of the trajectories followed by a quantum harmonic oscillator coupled to $N$ dissipative baths by using an approach to large-deviation theory inspired by phase-space quantum optics. As an illustrative example, we study the archetypal case of a har…

[Phys. Rev. A 92, 013844] Published Fri Jul 24, 2015

]]>For continuous weak measurements of qubits, we obtain exact expressions for weak values (WVs) from the postselection restricted average of measurement outputs, by using both the quantum-trajectory equation (QTE) and the quantum Bayesian approach. The former is applicable to short-time weak measureme…

[Phys. Rev. A 92, 012119] Published Thu Jul 23, 2015

]]>Considering the evolution of the quantum state of a pair of entangled photons in a turbulent atmosphere and using the quadratic approximation to the Kolmogorov model of turbulence, we provide an analytical solution for the dynamical equation (an infinitesimal propagation equation) that describes thi…

[Phys. Rev. A 92, 012326] Published Thu Jul 23, 2015

]]>We have measured the relative probability for the production of ${\mathrm{N}}_{2}{}^{2+}$ using monochromatized synchrotron radiation in the range of 38 to 400 eV. We find the energy dependence of the ratio ${\mathrm{N}}_{2}{}^{2+}/{\mathrm{N}}_{2}{}^{+}$ to be very similar to that of the ${\mathrm{He}}^{2+}/{\mathrm{He}}^{+}$ ratio, which indicates a similarity in the double-photoionizat…

[Phys. Rev. A 92, 013421] Published Thu Jul 23, 2015

]]>We theoretically analyze quasi-one-dimensional Bose-Einstein condensates under the influence of a harmonic trap and a narrow potential defect that moves through the atomic cloud. Performing simulations on the mean-field level, we explore a robust mechanism in which a single dark soliton is nucleated…

[Phys. Rev. A 92, 013627] Published Thu Jul 23, 2015

]]>Confined quantum systems involving $N$ identical interacting fermions are found in many areas of physics, including condensed matter, atomic, nuclear, and chemical physics. In a previous series of papers, a many-body perturbation method that is applicable to both weakly and strongly interacting system…

[Phys. Rev. A 92, 013628] Published Thu Jul 23, 2015

]]>In this report we study the Vernier effect in coupled laser systems consisting of two cavities. We show that depending on the nature of their coupling, not only can the “supermodes” formed at overlapping resonances of these two cavities have the lowest thresholds as previously found, leading to lasi…

[Phys. Rev. A 92, 013840] Published Thu Jul 23, 2015

]]>We show that the role of the Lyapunov exponents can be extended beyond the customary local instability, such as limit cycle behavior, to include its use as an evolutionary predictor of the dynamics of a laser with injected signal (LIS). Numerical studies of LIS reveal that as a function of the input…

[Phys. Rev. A 92, 013841] Published Thu Jul 23, 2015

]]>Nanoparticle-induced modifications of the spectrum of whispering-gallery modes (WGMs) of optical spheroidal resonators are studied theoretically. Combining an *ab initio* solution of a single-resonator problem with a dipole approximation for the particle, we derive simple analytical expressions for fr…

[Phys. Rev. A 92, 013842] Published Thu Jul 23, 2015

]]>We derive a generalized wave-particle duality relation for arbitrary multipath quantum interference phenomena. Beyond the conventional notion of the wave nature of a quantum system, i.e., the interference fringe visibility, we introduce a quantifier as the normalized quantum coherence, recently def…

[Phys. Rev. A 92, 012118] Published Wed Jul 22, 2015

]]>High-order-harmonic generation (HHG) for the ${{\mathrm{H}}_{2}}^{+}$ molecule in a 3-fs, 800-nm few-cycle Gaussian laser pulse combined with a static field is investigated by solving the one-dimensional electronic and one-dimensional nuclear time-dependent Schrödinger equation within the non-Born-Oppenheimer approximat…

[Phys. Rev. A 92, 013418] Published Wed Jul 22, 2015

]]>Trapping a large number of ${}^{6}\mathrm{Li}$ atoms in a simplified experimental setup is a long-term pursuit in the studies of degenerate Fermi gases. We experimentally and theoretically demonstrate the enhancement of ${}^{6}\mathrm{Li}$ trapping efficiency in a three-dimensional magneto-optical trap (3D MOT) by using the multip…

[Phys. Rev. A 92, 013419] Published Wed Jul 22, 2015

]]>We examine the residual current to investigate the conversion efficiency from the few-cycle laser pulse into the terahertz radiation of ${\text{H}}_{2}{}^{+}$ by solving the time-dependent Schrödinger equation in the non-Born-Oppenheimer approach. It is found that the nuclear motion and high vibrational states will im…

[Phys. Rev. A 92, 013420] Published Wed Jul 22, 2015

]]>We present a theoretical description of the radio-frequency (rf) spectroscopy of fermionic atomic gases, based on the second-order response theory at finite temperature. This approach takes into account the energy resolution due to the envelope of the rf pulse. For a noninteracting final state, the …

[Phys. Rev. A 92, 013626] Published Wed Jul 22, 2015

]]>We report the observation of diffraction cancellation for visible beams with widths from tens of wavelengths down to fractions of the optical wavelength. The phenomenon is observed at the transition from diffraction- to antidiffraction-dominated beam propagation, triggered by a thermal shock in a ph…

[Phys. Rev. A 92, 013835] Published Wed Jul 22, 2015

]]>Recent theoretical studies of stimulated Brillouin scattering (SBS) in nanoscale devices have led to intense research effort dedicated to the demonstration and application of this nonlinearity in on-chip systems. The key feature of SBS in integrated photonic waveguides is that small, high-contrast w…

[Phys. Rev. A 92, 013836] Published Wed Jul 22, 2015

]]>A method capable of accessing the ultra-small-angle x-ray-scattering distribution of a sample from two-dimensional raster scans is developed, which promises to have applications in various fields of material science as well as biological imaging.

[Phys. Rev. A 92, 013837] Published Wed Jul 22, 2015

]]>We study the coherent effect of the Casimir-Polder interaction on the oscillations of two-photon driven atoms. We find that, for oscillations between two degenerate states in $\mathrm{\Lambda}$ configuration, shifts on the Rabi frequency may be induced by nonadditive level shifts. For oscillations between two Rydber…

[Phys. Rev. A 92, 013838] Published Wed Jul 22, 2015

]]>The so-called spin Hall effect of light, the transverse splitting of the left circularly polarized and right circularly polarized components of light with initially linear polarization, is investigated, and the coherent superposition of two sub-components with different shifts in each component that leads to the observed phenomena is elucidated.

[Phys. Rev. A 92, 013839] Published Wed Jul 22, 2015

]]>The measurement fidelity of superconducting transmon and Xmon qubits is partially limited by the qubit energy relaxation through the resonator into the transmission line, which is also known as the Purcell effect. One way to suppress this energy relaxation is to employ a filter which impedes microwa…

[Phys. Rev. A 92, 012325] Published Tue Jul 21, 2015

]]>Ionization energies for the ground state of berylliumlike ions with nuclear charge numbers in the range $16\le Z\le 96$ are rigorously evaluated. The calculations merge the *ab initio* QED treatment in the first and second orders of the perturbation theory in the fine-structure constant $\alpha $ with the third- and …

[Phys. Rev. A 92, 012514] Published Tue Jul 21, 2015

]]>We theoretically study the control of the interferences of multiple tunneling photoelectron wave packets in both temporal and spatial domains by an orthogonally polarized two-color laser pulse. Profound carpetlike and stripelike interference patterns can be turned on or off in the momentum spectra u…

[Phys. Rev. A 92, 013416] Published Tue Jul 21, 2015

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