We investigate the extreme dynamics of non-Hermitian systems near higher-order exceptional points in photonic networks constructed using the bosonic algebra method. We show that strong power oscillations for certain initial conditions can occur as a result of the peculiar eigenspace geometry and its...

[Phys. Rev. A 97, 020105(R)] Published Thu Feb 22, 2018

]]>The distribution of noncollinear magnetism in an electronic system provides information about the kinetic energy as well as some kinetic energy densities. Two different everywhere-positive kinetic densities related to the Schrödinger-Pauli Hamiltonian are considered. For one-electron systems describ...

[Phys. Rev. A 97, 022513] Published Thu Feb 22, 2018

]]>Fast (${E}_{0}=520\phantom{\rule{0.16em}{0ex}}\mathrm{eV}$) electron-impact ionization of molecular hydrogen (${\mathrm{H}}_{2}$) is studied experimentally and theoretically for a resolved molecular axis angle and 10 eV ejected electron energy. Fully differential cross sections were measured using an electron-electron-ion triple coincidence experiment in whi...

[Phys. Rev. A 97, 022706] Published Thu Feb 22, 2018

]]>We present a quantum many-body description of the excitation spectrum of Rydberg polarons in a Bose gas. The many-body Hamiltonian is solved with a functional determinant approach, and we extend this technique to describe Rydberg polarons of finite mass. Mean-field and classical descriptions of the ...

[Phys. Rev. A 97, 022707] Published Thu Feb 22, 2018

]]>We describe the emergence of strong spatial correlations, akin to liquidlike behavior and crystallization effects, in low- (one- and two-)dimensional gases of cold Rydberg atoms. The presence of an external electric field permanently polarizes the atoms, which became highly correlated due to the lon...

[Phys. Rev. A 97, 022708] Published Thu Feb 22, 2018

]]>Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribu...

[Phys. Rev. A 97, 023418] Published Thu Feb 22, 2018

]]>The fragmentation of gas phase endohedral fullerene, $\mathrm{H}{\mathrm{o}}_{3}\mathrm{N}@{\mathrm{C}}_{80}$, was investigated using femtosecond near-infrared laser pulses with an ion velocity map imaging spectrometer. We observed that $\mathrm{H}{\mathrm{o}}^{+}$ abundance associated with carbon cage opening dominates at an intensity of $1.1\times {10}^{14}\phantom{\rule{0.16em}{0ex}}\mathrm{W}/\mathrm{c}{\mathrm{m}}^{2}$. As the intensity ...

[Phys. Rev. A 97, 023419] Published Thu Feb 22, 2018

]]>We studied the ground state of alkaline-earth-metal atoms confined in one-dimensional optical lattices with an effective hybridization generated by a suitable laser field. This system is modeled by the periodic Anderson model plus a quadratic confining potential, and we adopted the density-matrix re...

[Phys. Rev. A 97, 023630] Published Thu Feb 22, 2018

]]>We investigated a one-dimensional system of anyons that interact with each other under a local three-body term. Using a fractional Jordan-Wigner transformation, we arrived at a modified Bose-Hubbard model, which exhibits gapped and gapless phases. We built the phase diagram of the system fixing the ...

[Phys. Rev. A 97, 023631] Published Thu Feb 22, 2018

]]>We describe how color superfluidity is modified in the presence of color-flip and color-orbit fields in the context of ultracold atoms and discuss connections between this problem and that of color superconductivity in quantum chromodynamics. We study the case of $s$-wave contact interactions between ...

[Phys. Rev. A 97, 023632] Published Thu Feb 22, 2018

]]>We study strong, light-mediated, resonant dipole-dipole interactions in two-dimensional planar lattices of cold atoms. We provide a detailed analysis for the description of the dipolar point emitter lattice plane as a “superatom” whose response is similar to electromagnetically induced transparency ...

[Phys. Rev. A 97, 023833] Published Thu Feb 22, 2018

]]>In an anisotropic medium, the refractive index depends on the direction of propagation. Zero index in a fixed direction implies a stretching of the wave to uniformity along that axis, reducing the effective number of dimensions by 1. Here we investigate two-dimensional gyrotropic media where the ref...

[Phys. Rev. A 97, 023834] Published Thu Feb 22, 2018

]]>We consider the propagation of both fully coherent and partially coherent complex scalar fields, through linear shift-invariant imaging systems. The state of such imaging systems is characterized by a countable infinity of aberration coefficients, the values for which can be viewed as coordinates fo...

[Phys. Rev. A 97, 023835] Published Thu Feb 22, 2018

]]>Measurements performed on distant parts of an entangled quantum state can generate correlations incompatible with classical theories respecting the assumption of local causality. This is the phenomenon known as quantum nonlocality that, apart from its fundamental role, can also be put to practical u...

[Phys. Rev. A 97, 022111] Published Wed Feb 21, 2018

]]>A quantum observable and a channel are considered compatible if they form parts of the same measurement device, otherwise they are incompatible. Constrains on compatibility between observables and channels can be quantified via relations highlighting the necessary tradeoffs between noise and disturb...

[Phys. Rev. A 97, 022112] Published Wed Feb 21, 2018

]]>A periodically driven multiple-parametric two-level model is introduced. Under certain special parameter conditions, an exact analytical solution to this model can be obtained in an explicit form. This gives an exact analytical demonstration of the well-known Landau-Zener-Stückelberg-Majorana resona...

[Phys. Rev. A 97, 022113] Published Wed Feb 21, 2018

]]>We investigate the quantum interference induced shifts between energetically close states in highly charged ions, with the energy structure being observed by laser spectroscopy. In this work, we focus on hyperfine states of lithiumlike heavy-$Z$ isotopes and quantify how much quantum interference chan...

[Phys. Rev. A 97, 022510] Published Wed Feb 21, 2018

]]>We present in this paper a theory of dynamic polarizability for an atomic state due to an external field of nonparaxial Laguerre-Gaussian (LG) beam using the sum-over-states technique. A highly correlated relativistic coupled-cluster theory is used to evaluate the most important and correlation-sens...

[Phys. Rev. A 97, 022511] Published Wed Feb 21, 2018

]]>Roles of electron correlation effects in the determination of attachment energies, magnetic-dipole hyperfine-structure constants, and electric-dipole $\left(E1\right)$ matrix elements of the low-lying states in the singly charged cadmium ion $\left({\mathrm{Cd}}^{+}\right)$ have been analyzed. We employ the singles and doubles approximate...

[Phys. Rev. A 97, 022512] Published Wed Feb 21, 2018

]]>We study the quadratic Zeeman effect (QZE) in a system of antiferromagnetic spin-1 bosons on a square lattice and derive the ground-state phase diagrams by means of quantum Monte Carlo simulations and mean-field treatment. The QZE imbalances the populations of the magnetic sublevels $\sigma =\pm 1$ and $\sigma =0$, an...

[Phys. Rev. A 97, 023628] Published Wed Feb 21, 2018

]]>Nanomaterials, which show large reflectivity for external radiation, are of general interest in science and technology. We report a result from our ongoing research on the reflection of low-energy neutrons from powders of detonation diamond nanoparticles. Our previous work showed a large probability...

[Phys. Rev. A 97, 023629] Published Wed Feb 21, 2018

]]>I present a semiclassical analysis of a spatial-mode demultiplexing (SPADE) measurement scheme for far-field incoherent optical imaging under the effects of diffraction and photon shot noise. Building on previous results that assume two point sources or the Gaussian point-spread function, I generali...

[Phys. Rev. A 97, 023830] Published Wed Feb 21, 2018

]]>We report nonclassical aspects of the collective behavior of two atoms in a cavity by investigating the photon statistics and photon distribution over a very broad domain of parameters. Starting with the dynamics of two atoms radiating in phase into the cavity, we study the photon statistics for arb...

[Phys. Rev. A 97, 023831] Published Wed Feb 21, 2018

]]>There is a common understanding in quantum optics that nonclassical states of light are states that do not have a positive semidefinite and sufficiently regular Glauber-Sudarshan $P$ function. Almost all known nonclassical states have $P$ functions that are highly irregular, which makes working with the...

[Phys. Rev. A 97, 023832] Published Wed Feb 21, 2018

]]>[Phys. Rev. A 97, 029904] Published Wed Feb 21, 2018

]]>[Phys. Rev. A 97, 029905] Published Wed Feb 21, 2018

]]>We study the quantum Zeno effect (QZE) and quantum anti-Zeno effect (QAZE) in a two-level system (TLS) interacting with an environment that has $1/f$ noise. Using a numerically exact method based on the thermofield dynamics theory and the matrix product states, we obtain exact evolutions of the TLS an...

[Phys. Rev. A 97, 022108] Published Tue Feb 20, 2018

]]>We analyze families of measures for the quantum statistical speed which include as special cases the quantum Fisher information, the trace speed, i.e., the quantum statistical speed obtained from the trace distance, and more general quantifiers obtained from the family of Schatten norms. These measu...

[Phys. Rev. A 97, 022109] Published Tue Feb 20, 2018

]]>Einstein-Podolsky-Rosen steering is a form of quantum nonlocality, which is weaker than Bell nonlocality, but stronger than entanglement. Here we present a method to check Einstein-Podolsky-Rosen steering in the scenario where the steering party performs two black-box measurements and the trusted pa...

[Phys. Rev. A 97, 022110] Published Tue Feb 20, 2018

]]>Covert communication allows the transmission of messages in such a way that it is not possible for adversaries to detect that the communication is occurring. This provides protection in situations where knowledge that two parties are talking to each other may be incriminating to them. In this work, ...

[Phys. Rev. A 97, 022325] Published Tue Feb 20, 2018

]]>We consider the bipartite state of a two-photon polarization system and obtain the exact analytical expression for the von Neumann entropy in the particular case of a five-parameter polarization density matrix. We investigate and graphically illustrate the dependence of the entropy on these five par...

[Phys. Rev. A 97, 022326] Published Tue Feb 20, 2018

]]>We investigate how to manipulate the tripartite frequency correlation of triplets which are generated from cascaded spontaneous parametric down-conversions. A monolithic quadratic nonlinear crystal is designed to contain two segments of periodically poled lithium niobate waveguide as nonlinear mediu...

[Phys. Rev. A 97, 022327] Published Tue Feb 20, 2018

]]>We demonstrate a method for general linear optical networks that allows one to factorize any $\mathrm{SU}(n$) matrix in terms of two $\mathrm{SU}(n-1)$ blocks coupled by an SU(2) entangling beam splitter. The process can be recursively continued in a straightforward way, ending in a tidy arrangement of SU(2) transformati...

[Phys. Rev. A 97, 022328] Published Tue Feb 20, 2018

]]>We propose general methodology of deterministic single-mode quantum interaction nonlinearly modifying single quadrature variable of a continuous-variable system. The methodology is based on linear coupling of the system to ancillary systems subsequently measured by quadrature detectors. The nonlinea...

[Phys. Rev. A 97, 022329] Published Tue Feb 20, 2018

]]>We theoretically study the Casimir-Polder force on an atom in an arbitrary initial state in a rather general electromagnetic environment wherein the materials may have a nonreciprocal bianisotropic dispersive response. It is shown that under the Markov approximation the force has resonant and nonres...

[Phys. Rev. A 97, 022509] Published Tue Feb 20, 2018

]]>The tunneling reaction ${\mathrm{H}}_{2}+{\mathrm{D}}^{-}\to \mathrm{HD}+{\mathrm{H}}^{-}$ was studied in a recent experimental work at low temperatures (10, 19, and 23 K) by Endres *et al.* [Phys. Rev. A **95**, 022706 (2017)]. An upper limit of the rate coefficient was found to be about ${10}^{-18}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{3}$/s. In the present study, reaction probabilities are determined ...

[Phys. Rev. A 97, 022705] Published Tue Feb 20, 2018

]]>Strong-field ionization (SFI) of the homonuclear noble gas dimer ${\mathrm{Xe}}_{2}$ is investigated and compared with SFI of the Xe atom and of the ArXe heteronuclear dimer by using ultrashort Ti:sapphire laser pulses and photoelectron momentum spectroscopy. The large separation of the two nuclei of the dimer allo...

[Phys. Rev. A 97, 023417] Published Tue Feb 20, 2018

]]>The attractive two-site Bose-Hubbard model is studied within the framework of the analytical solution obtained by the application of the quantum inverse scattering method. The structure of the ground and excited states is analyzed in terms of solutions of Bethe equations, and an approximate solution...

[Phys. Rev. A 97, 023626] Published Tue Feb 20, 2018

]]>Considerable theoretical and experimental efforts have been devoted to the quench dynamics, in particular, the dynamical quantum phase transition (DQPT) and the steady-state transition. These developments have motivated us to study the quench dynamics of the topological systems, from which we find t...

[Phys. Rev. A 97, 023627] Published Tue Feb 20, 2018

]]>We address an experimental scheme to analyze the optical bistability and the entanglement of two movable mirrors coupled to a two-mode laser inside a doubly resonant cavity. With this aim we investigate the master equations of the atom-cavity subsystem in conjunction with the quantum Langevin equati...

[Phys. Rev. A 97, 023829] Published Tue Feb 20, 2018

]]>Relations among the concepts of measurement, information, and physical reality are established with the quantification of the degree of reality of an observable for a given preparation. It is found that for pure states the entanglement with the apparatus precisely determines the amount by which the reality of the monitored observable increases.

[Phys. Rev. A 97, 022107] Published Fri Feb 16, 2018

]]>We study photoelectron holography in strong bicircular two-color laser fields by solving the time-dependent Schrödinger equation (TDSE) and a semiclassical rescattering model with implementing interference effect. The holographic patterns observed in the TDSE are well recaptured by the semiclassical...

[Phys. Rev. A 97, 023415] Published Fri Feb 16, 2018

]]>We propose and analyze an electrostatic-optical nanoscale trap for cold diatomic polar molecules. The main ingredient of our proposal is a square array of ferroelectric nanorods with alternating polarization. We show that, in contrast to electrostatic traps using the linear Stark effect, a quadratic...

[Phys. Rev. A 97, 023416] Published Fri Feb 16, 2018

]]>Fingering instabilities and pattern formation are studied at the interface of an oppositely polarized two-component Bose-Einstein condensate with strong dipole-dipole interactions in three dimensions. It is shown that the rotational symmetry is spontaneously broken by fingering instability when the dipole-dipole interactions are strengthened.

[Phys. Rev. A 97, 023625] Published Fri Feb 16, 2018

]]>The coupling of atomic arrays and one-dimensional subwavelength waveguides gives rise to interesting photon transport properties, such as recent experimental demonstrations of large Bragg reflection, and paves the way for a variety of potential applications in the field of quantum nonlinear optics. ...

[Phys. Rev. A 97, 023827] Published Fri Feb 16, 2018

]]>When two identical (coherent) beams are injected at a semi-infinite non-Hermitian medium from left and right, we show that both reflection $({r}_{L},{r}_{R})$ and transmission $({t}_{L},{t}_{R})$ amplitudes are nonreciprocal. In a parametric domain, there exists spectral singularity (SS) at a real energy $E={E}_{*}={k}_{*}^{2}$ and the d...

[Phys. Rev. A 97, 023828] Published Fri Feb 16, 2018

]]>[Phys. Rev. A 97, 029903] Published Fri Feb 16, 2018

]]>We introduce an entanglement-depth criterion optimized for planar quantum-squeezed (PQS) states. It is connected with the sensitivity of such states for estimating a phase generated by rotations about an axis orthogonal to its polarization. We compare numerically our criterion with the well-known ex...

[Phys. Rev. A 97, 020301(R)] Published Thu Feb 15, 2018

]]>The electric-field noise affecting quantum logic gates in surface-electrode ion traps is studied as a function of trapping frequency, electrode temperature, and distance $d$ between ion and surface. The finding that the noise scales as $1/{d}^{4}$ eliminates various surface-noise models that have been proposed to explain the anomalous ion heating observed in this type of trap.

[Phys. Rev. A 97, 020302(R)] Published Thu Feb 15, 2018

]]>Most research regarding quantum adiabatic optimization has focused on stoquastic Hamiltonians, whose ground states can be expressed with only real non-negative amplitudes and thus for whom destructive interference is not manifest. This raises the question of whether classical Monte Carlo algorithms ...

[Phys. Rev. A 97, 022323] Published Thu Feb 15, 2018

]]>We propose and investigate a method of error detection and noise correction for bosonic linear networks using a method of unitary averaging. The proposed error averaging does not rely on ancillary photons or control and feedforward correction circuits, remaining entirely passive in its operation. We...

[Phys. Rev. A 97, 022324] Published Thu Feb 15, 2018

]]>We report measurements of the scalar and tensor static polarizabilities of the ${}^{115}\mathrm{In}\phantom{\rule{4pt}{0ex}}7{p}_{1/2}$ and $7{p}_{3/2}$ excited states using two-step diode laser spectroscopy in an atomic beam. These scalar polarizabilities are one to two orders of magnitude larger than for lower-lying indium states due to the close pr...

[Phys. Rev. A 97, 022507] Published Thu Feb 15, 2018

]]>The theory is developed for one- and two-atom interactions when the atom has a Rydberg electron attached to a hyperfine-split core state. This situation is relevant for some of the rare-earth and alkaline-earth atoms that have been proposed for experiments on Rydberg-Rydberg interactions. For the ra...

[Phys. Rev. A 97, 022508] Published Thu Feb 15, 2018

]]>We explore theoretically the generation and all-optical control of optical frequency combs (OFCs) in photon transmission based on a combination of single-atom-cavity quantum electrodynamics (CQED) and electromagnetically induced transparency (EIT). Here an external control field is used to form the ...

[Phys. Rev. A 97, 023826] Published Thu Feb 15, 2018

]]>We investigate the quantum annealing of the ferromagnetic $p$-spin model in a dissipative environment ($p=5$ and $p=7$). This model, in the large-$p$ limit, codifies Grover's algorithm for searching in an unsorted database [L. K. Grover, Proceedings of the 28th Annual ACM Symposium on Theory of Computing (A...

[Phys. Rev. A 97, 022319] Published Wed Feb 14, 2018

]]>A method is developed to analyze the performance of sequential measurements, thus providing a way to benchmark various optical receivers. In particular, it is proved that a Dolinar-like receiver cannot realize a “minimum error quantum measurement” when dealing with ternary coherent states.

[Phys. Rev. A 97, 022320] Published Wed Feb 14, 2018

]]>We investigate the generation of entanglement between two noninteracting qubits coupled to a common reservoir. An experimental setup was conceived to encode one qubit on the polarization of an optical beam and another qubit on its transverse mode. The action of the reservoir is implemented as condit...

[Phys. Rev. A 97, 022321] Published Wed Feb 14, 2018

]]>We implement an embedding quantum simulator (EQS) in nuclear spin systems. The experiment consists of a simulator of up to three qubits, plus a single ancillary qubit, where we are able to efficiently measure the concurrence and the three-tangle of two-qubit and three-qubit systems as they undergo e...

[Phys. Rev. A 97, 022322] Published Wed Feb 14, 2018

]]>We present measurements of photon absorption by free electrons as a solid is transformed to plasma. A femtosecond x-ray free-electron laser is used to heat a solid, which separates the electron and ion heating time scales. The changes in absorption are measured with an independent probe pulse create...

[Phys. Rev. A 97, 023414] Published Wed Feb 14, 2018

]]>We study the nonlinear dynamics of trapped-ion models far away from the Lamb-Dicke regime. This nonlinearity induces a blockade on the propagation of quantum information along the Hilbert space of the Jaynes-Cummings and quantum Rabi models. We propose to use this blockade as a resource for the diss...

[Phys. Rev. A 97, 023624] Published Wed Feb 14, 2018

]]>We demonstrate a different scheme to perform optical sectioning of a sample based on the concept of induced coherence [Zou *et al.*, Phys. Rev. Lett. **67**, 318 (1991)]. This can be viewed as a different type of optical coherence tomography scheme where the varying reflectivity of the sample along the d...

[Phys. Rev. A 97, 023824] Published Wed Feb 14, 2018

]]>We investigate a class of isodiffracting pulsed beams, which are superpositions of transverse modes supported by spherical-mirror laser resonators. By employing modal weights that, for stationary light, produce a Gaussian Schell-model beam, we extend this standard model to pulsed beams. We first con...

[Phys. Rev. A 97, 023825] Published Wed Feb 14, 2018

]]>Wang and Knowles (WK) [Phys. Rev. A **92**, 012520 (2015)] have given a counterexample to the conventional in reduced density-matrix functional theory representation of the second-order reduced density matrix (2RDM) ${\mathrm{\Gamma}}_{ij,kl}$ in the basis of the natural orbitals as a function ${\mathrm{\Gamma}}_{ij,kl}\left(n\right)$ of the orbital occup...

[Phys. Rev. A 97, 026501] Published Wed Feb 14, 2018

]]>It is shown that symmetry considerations do not alter the conclusions of our original work [Phys. Rev. A **92**, 012520 (2015)], and that there exists an example of an electronic system for which at several geometries the one-matrix eigenvalues are identical, but the two-matrix spectrum is not. It is st...

[Phys. Rev. A 97, 026502] Published Wed Feb 14, 2018

]]>The spinor dynamics of Bose-Einstein condensates of ${}^{87}\mathrm{Rb}$ atoms with hyperfine spins of 1 and 2 are investigated. A mixture of spinor condensates is generated in the transversely polarized spin-1 and the longitudinally polarized spin-2 states using simultaneous Ramsey interferometry. In the subsequen...

[Phys. Rev. A 97, 021602(R)] Published Tue Feb 13, 2018

]]>Recently, it has been shown that energy can be deposited on a collection of quantum systems at a rate that scales superextensively. Some of these schemes for quantum batteries rely on the use of global many-body interactions that take the batteries through a correlated shortcut in state space. Here ...

[Phys. Rev. A 97, 022106] Published Tue Feb 13, 2018

]]>In this paper we propose a scheme for coherent control and storage of a microwave pulse in superconducting circuits exploiting the idea of electromagnetically induced transparency (EIT) and the Aulter-Townes (AT) effect. We show that superconducting artificial atoms in a four-level tripod configurat...

[Phys. Rev. A 97, 022318] Published Tue Feb 13, 2018

]]>Quantum information theory is employed in quantum chemical computations of molecular potentials to analyze the effects of electron correlation. This study may pave the way to techniques that may help find active Hilbert space in such computations more efficiently.

[Phys. Rev. A 97, 022505] Published Tue Feb 13, 2018

]]>A precision comparison of theory and experiments on the $g$ factor of an electron bound in a hydrogenlike ion with a spinless nucleus requires a detailed account of finite-nuclear-size contributions. While the relativistic corrections to the leading finite-size contribution are known, the higher-order...

[Phys. Rev. A 97, 022506] Published Tue Feb 13, 2018

]]>Four-photon double detachment of the helium negative ion is investigated experimentally and theoretically for photon energies where the transient helium atom is in the $1s2s\phantom{\rule{0.16em}{0ex}}{}^{3}S$ or $1s2p\phantom{\rule{0.16em}{0ex}}{}^{3}P^{\mathrm{o}}$ states, which subsequently ionize by absorption of three photons. Ionization is enhanced by intermediate resonance...

[Phys. Rev. A 97, 023412] Published Tue Feb 13, 2018

]]>We employ the $R$ matrix with time dependence method to investigate extreme-ultraviolet-initiated high-order harmonic generation (XIHHG) in ${\mathrm{Ar}}^{+}$. Using a combination of extreme-ultraviolet (XUV, 92 nm, $3\times {10}^{12}\phantom{\rule{0.28em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{-2}$) and time-delayed, infrared (IR, 800 nm, $3\times {10}^{14}\phantom{\rule{0.28em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{-2}$) laser pulses, we demonstrate that c...

[Phys. Rev. A 97, 023413] Published Tue Feb 13, 2018

]]>We show that a conspicuous wave packet of ultracold noninteracting bosonic atoms emerges in a one-dimensional parabolic optical lattice as in the setup of the Aarhus experiment [P. L. Pedersen, M. Gajdacz, N. Winter, A. J. Hilliard, J. F. Sherson, and J. Arlt, Phys. Rev. A **88**, 023620 (2013)], given ...

[Phys. Rev. A 97, 023620] Published Tue Feb 13, 2018

]]>We discuss the cooling dynamics of heavy impurity atoms in a Bose-Einstein condensate (BEC) by emission of Cherenkov phonons from scattering with the condensate. In a weakly interacting low-temperature condensate, different scattering processes result in a separation of time scales of the thermaliza...

[Phys. Rev. A 97, 023621] Published Tue Feb 13, 2018

]]>We investigate the ground-state phases of a mixture of spin-1 and spin-2 Bose-Einstein condensates at zero magnetic field. In addition to the intraspin interactions, two spin-dependent interaction coefficients are introduced to describe the interspin interaction. We systematically explore the wide p...

[Phys. Rev. A 97, 023622] Published Tue Feb 13, 2018

]]>We present measurements of interspecies Feshbach resonances and subsequent creation of dual-species Bose-Einstein condensates of ${}^{23}\mathrm{Na}$ and ${}^{39}\mathrm{K}$. We prepare both optically trapped ensembles in the spin state $\left|f=1,{m}_{f}=-1\right.\u232a$ and perform atom loss spectroscopy in a magnetic field range from $0$ to $700\phantom{\rule{0.16em}{0ex}}\mathrm{G}$. The obse...

[Phys. Rev. A 97, 023623] Published Tue Feb 13, 2018

]]>The photonic router is a key device in optical quantum networks. Conventional routers, however, can only transfer a photon from the input port to the desired port probabilistically. Here, we propose to use chiral photon-atom interactions for targeted routing that can transfer a single photon from th...

[Phys. Rev. A 97, 023821] Published Tue Feb 13, 2018

]]>Kerr nonlinearity in an optical coating is explored to generate photon pairs within a high-finesse Fabry-Perot resonator. The scheme, based on a continuous-wave diode laser, provides a robust and frequency-tunable quantum source.

[Phys. Rev. A 97, 023822] Published Tue Feb 13, 2018

]]>The quantum interference of entangled photons forms a key phenomenon underlying various quantum-optical technologies. It is known that the quantum interference patterns of entangled photon pairs can be reconstructed classically by the time-reversal method; however, the time-reversal method has been ...

[Phys. Rev. A 97, 023823] Published Tue Feb 13, 2018

]]>[Phys. Rev. A 97, 029902] Published Tue Feb 13, 2018

]]>We model the bang-bang optimization protocol as a shortcut to adiabaticity in the ground-state preparation of a trapped-ion quantum simulator. Compared to a locally adiabatic evolution, the bang-bang protocol typically produces a lower ground-state probability, but its implementation is so much simp...

[Phys. Rev. A 97, 022313] Published Mon Feb 12, 2018

]]>We study the problem of locally distinguishing pure quantum states using shared entanglement as a resource. For a given set of locally indistinguishable states, we define a resource state to be useful if it can enhance local distinguishability and optimal if it can distinguish the states as well as ...

[Phys. Rev. A 97, 022314] Published Mon Feb 12, 2018

]]>With the significant advancement in quantum computation during the past couple of decades, the exploration of machine-learning subroutines using quantum strategies has become increasingly popular. Gaussian process regression is a widely used technique in supervised classical machine learning. Here w...

[Phys. Rev. A 97, 022315] Published Mon Feb 12, 2018

]]>For supporting practical quantum key distribution (QKD), it is critical to stabilize the physical parameters of signals, e.g., the intensity, phase, and polarization of the laser signals, so that such QKD systems can achieve better performance and practical security. In this paper, an approach is de...

[Phys. Rev. A 97, 022316] Published Mon Feb 12, 2018

]]>Recently it was shown that the growth of entanglement in an initially separable state, as measured by the purity of subsystems, can be characterized by a timescale that takes a universal form for any Hamiltonian. We show that the same timescale governs the growth of entanglement for all Rényi entrop...

[Phys. Rev. A 97, 022317] Published Mon Feb 12, 2018

]]>We consider a nonrelativistic approximation for the neutral muonic helium atom, a three-body system, which consists of an electron, a muon, and a helium nucleus. We discuss the case with the muon in the ground state and study the low energy levels and the transition frequencies of the electron ($2s-1\mathrm{...}$

[Phys. Rev. A 97, 022504] Published Mon Feb 12, 2018

]]>Fano models—consisting of a Hamiltonian with a discrete-continuous spectrum—are one of the basic toy models in spectroscopy. They have been successful in explaining the line shape of experiments in atomic physics and condensed matter. These models, however, have largely been beyond the scope of diss...

[Phys. Rev. A 97, 023411] Published Mon Feb 12, 2018

]]>We derive a general and exact equation of motion for a quantized vortex in an inhomogeneous two-dimensional Bose-Einstein condensate. This equation expresses the velocity of a vortex as a sum of local ambient density and phase gradients in the vicinity of the vortex. We perform Gross-Pitaevskii simu...

[Phys. Rev. A 97, 023617] Published Mon Feb 12, 2018

]]>One-dimensional superlattices with periodic spatial modulations of onsite potentials or tunneling coefficients can exhibit a variety of properties associated with topology or symmetry. Recent developments of ring-shaped optical lattices allow a systematic study of those properties in superlattices w...

[Phys. Rev. A 97, 023618] Published Mon Feb 12, 2018

]]>Recent experiments have illustrated that long-range two-body interactions can be induced by laser coupling atoms to highly excited Rydberg states. Stimulated by this achievement, we study the supersolidity of lattice bosons in an experimentally relevant situation. In our setup, we consider two-compo...

[Phys. Rev. A 97, 023619] Published Mon Feb 12, 2018

]]>People have been paying attention to the role of atoms' complex internal level structures in the research of electromagnetically induced transparency (EIT) for a long time, where the various degenerate Zeeman levels usually generate complex linkage patterns for the atomic transitions. It turns out, ...

[Phys. Rev. A 97, 023815] Published Mon Feb 12, 2018

]]>We consider the nonstationary circuit QED architecture in which a single-mode cavity interacts with $N>1$ identical qubits, and some system parameters undergo a weak external perturbation. It is shown that in the dispersive regime one can engineer the two-photon exchange interaction by adjusting th...

[Phys. Rev. A 97, 023816] Published Mon Feb 12, 2018

]]>An algorithm to extract phases with dislocations from intensity measurements is proposed, and demonstrated on paraxial wave fields. The proposed algorithm makes use of the partial Fourier transformation which does not conserve the longitudinal orbital angular momentum and hence can create or destroy...

[Phys. Rev. A 97, 023817] Published Mon Feb 12, 2018

]]>We propose two experimental schemes for producing coherent-state superpositions which approximate different nonclassical states conditionally in traveling optical fields. Although these setups are constructed of a small number of linear optical elements and homodyne measurements, they can be used to...

[Phys. Rev. A 97, 023818] Published Mon Feb 12, 2018

]]>Emerging photonic, sensing, and quantum applications require high fields and tight localization but low power consumption. Spatial, spectral, and magnitude control of electromagnetic fields is of key importance for enabling experiments in atomic, molecular, and optical physics. We introduce the conc...

[Phys. Rev. A 97, 023819] Published Mon Feb 12, 2018

]]>We consider two-dimensional waveguide arrays with anisotropic coupling coefficients. We show using numerical and variational calculations that four stationary soliton types exist: site centered, bond centered, hybrid $X$, and hybrid $Y$. For the isotropic case the last two modes become identical and equ...

[Phys. Rev. A 97, 023820] Published Mon Feb 12, 2018

]]>We consider multitime correlators for output signals from linear detectors, continuously measuring several qubit observables at the same time. Using the quantum Bayesian formalism, we show that for unital (symmetric) evolution in the absence of phase backaction, an $N$-time correlator can be expressed...

[Phys. Rev. A 97, 020104(R)] Published Fri Feb 09, 2018

]]>We propose a method to interpolate dynamics of von Neumann and classical master equations with an arbitrary mixing parameter to investigate the thermal effects in quantum dynamics. The two dynamics are mixed by intervening to continuously modify their solutions, thus coupling them indirectly instead...

[Phys. Rev. A 97, 022312] Published Fri Feb 09, 2018

]]>The one- and two-electron Yukawa atoms, also referred to as the Debye-Hückel or screened Coulomb atoms, have been topics of considerable interest both for intrinsic reasons and because of their relevance to terrestrial and astrophysical plasmas. At sufficiently high screening the one-electron Yukawa...

[Phys. Rev. A 97, 022503] Published Fri Feb 09, 2018

]]>Experimental procedures for overcoming heating-induced trap losses and state leakage in scalable, nondestructive, and high-fidelity detection of the internal state of ${}^{87}$Rb atoms in optical dipole traps are presented. It is shown that off-resonant light is preferable for state detection in tightly confining optical potentials.

[Phys. Rev. A 97, 023410] Published Fri Feb 09, 2018

]]>We provide a description of the dynamic structure factor of a homogeneous unitary Fermi gas at low momentum and low frequency, based on the dissipative two-fluid hydrodynamic theory. The viscous relaxation time is estimated and is used to determine the regime where the hydrodynamic theory is applica...

[Phys. Rev. A 97, 023615] Published Fri Feb 09, 2018

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