Vacuum fluctuations of quantum fields provide an unavoidable environment for any quantum system coupled to it. We study the interplay between boundary conditions and acceleration in determining decoherence of a two-level Unruh-DeWitt detector coupled to a scalar field in a cylindrical cavity. We sho…

[Phys. Rev. A 114, 032209] Published Mon Sep 14, 2026

The theory of dynamical diffraction (DD) in perfect crystals is the backbone of high-precision neutron and x-ray diffraction experiments, enabling accurate determination of crystal-structure factors and the realization of perfect-crystal interferometers. In practice, however, real crystals exhibit d…

[Phys. Rev. A 114, 032210] Published Mon Sep 14, 2026

We formulate Zeno and anti-Zeno dynamics in a finite-memory reservoir as a time-domain measurement-filter problem. A two-level system exchanges an excitation with a finite chain of damped memory modes and is subjected to repeated partial, nonselective measurements. In the weak-coupling limit, the po…

[Phys. Rev. A 114, 032208] Published Fri Sep 11, 2026

In quantum position verification (QPV), a prover certifies her location to a set of verifiers by performing a quantum computation. One of the first QPV protocols was proposed by Kent, Munro, and Spiller in 2011: The prover receives a qubit $Q$ from one direction, receives an orthogonal basis $\{v,v^{\perp }\}$ fr…

[Phys. Rev. A 114, 032207] Published Thu Sep 10, 2026

Interference provides a fundamental mechanism for generating and manipulating entanglement in many-body quantum systems. Here, we develop an interference framework in which the nonlinear dynamics of collective spin-$\frac{1}{2}$ ensembles are mapped onto phase accumulation and self-interference in phase space,…

[Phys. Rev. A 114, 032206] Published Wed Sep 09, 2026

We study effective spin interactions arising from quantum electrodynamics scattering between localized fermionic spins. By integrating out photon and mediator fields, the dynamics reduce to an effective spin Hamiltonian. For two qubits in the nonrelativistic regime, the resulting interaction takes a…

[Phys. Rev. A 114, 032204] Published Tue Sep 08, 2026

Criticality-based quantum sensing exploits hypersensitive response to system parameters near phase transition points. This work uncovers two metrological advantages offered by topological phase transitions when the probe is prepared as topological edge states. First, the order of topological band to…

[Phys. Rev. A 114, 032205] Published Tue Sep 08, 2026

We investigate the variability of the quantum coherences of an arbitrary density matrix, in a given basis. An easily computable quantity that captures this variability notion is proposed and a dual relationship with an appropriate entropy is observed, with coherence dispersion (CD) being maximized f…

[Phys. Rev. A 114, 032202] Published Thu Sep 03, 2026

We find that the seemingly disparate control approaches for classical and quantum continuous-variable systems can be unified via differential manifolds of the ancillary representations. For classical systems, the ancillary representation is defined by the time-dependent ancillary canonical variables…

[Phys. Rev. A 114, 032203] Published Thu Sep 03, 2026

Quantum reference frame transformations have been proposed to provide a means by which to translate descriptions of quantum systems relative to each other. At present, there are several differing frameworks for describing quantum reference frames, with concomitantly different transformation rules. H…

[Phys. Rev. A 114, 032201] Published Wed Sep 02, 2026

We study two spatially separated boundary subsystems coupled to a common structured environment under relative motion within a Gaussian open-system framework. By integrating out the environment, we obtain an influence functional governed by a dressed environmental correlator evaluated at the boundar…

[Phys. Rev. A 114, 022218] Published Fri Aug 28, 2026

The authors reveal a fractional power-law decay in the spontaneous emission of a two-level system in the short- and long-time regimes. The fractional exponent is determined by the dispersion relation and spatial dimension of the environment.

[Phys. Rev. A 114, L020202] Published Tue Aug 25, 2026

In this work we investigate the effects of heat-bath-induced colored noise on nonreciprocal Landau-Zener tunneling. We perform numerical calculations of the instantaneous energy levels and find that noise induces stochastic fluctuations in these levels. Beyond such fluctuations, sufficiently large n…

[Phys. Rev. A 114, 022217] Published Mon Aug 24, 2026

We investigate the effective dynamics of a particle confined near a space curve. In the strict thin-layer reduction of the nondegenerate transverse ground state, torsion does not enter the local effective Hamiltonian, which contains only the curvature-induced scalar geometric potential. In contrast,…

[Phys. Rev. A 114, 022216] Published Fri Aug 21, 2026

We analyze Fock-state lattices (FSLs) from an algebraic viewpoint. Starting from a Lie algebra, we associate a FSL constructed from the action of its generators: diagonal (Cartan) generators define the lattice sites, while off-diagonal (root) generators determine the lattice bonds. This construction…

[Phys. Rev. A 114, 022214] Published Thu Aug 20, 2026

We present an exact spectral and dynamical analysis of continuous-time quantum walks on barbell graphs and two variants of star-of-cliques graphs, obtaining closed-form eigenvalues, eigenvectors, eigenstate inverse participation ratios (IPRs), and long-time dynamical IPRs ($\overline{\mathrm{IPR}}$) for all families and…

[Phys. Rev. A 114, 022215] Published Thu Aug 20, 2026

This study investigates the dynamics and phase of a nonreciprocal quantum multilevel spin system in Landau-Zener (LZ) transitions. Using Majorana's stellar representation, we analytically derive the solution for the LZ transition in a nonreciprocal quantum spin-$j$ model. Building on the results of th…

[Phys. Rev. A 114, 022212] Published Wed Aug 19, 2026

We present the formal derivation of a set of hierarchical equations of motion (HEOM) to compute system and environmental correlation functions in terms of a nonstationary underlying dynamics in complex time. This corresponds to partitioning the global validity of the HEOM spectral ansatz into local …

[Phys. Rev. A 114, 022213] Published Wed Aug 19, 2026

We explore the operation of quantum batteries in the Lipkin-Meshkov-Glick (LMG) model, when they are charged either through a sudden quench in the magnetic field strength or by coupling them to a single-mode bosonic charger. Through initializing the battery in either the symmetric or broken-symmetry…

[Phys. Rev. A 114, 022210] Published Tue Aug 18, 2026

The authors establish a relation between the conservation of coherence and the conservation of energy. They analyze partially coherent fields in the focal region of a converging lens, and show topological differences between the coherence flux and the energy flux.

[Phys. Rev. A 114, 022211] Published Tue Aug 18, 2026

Starting with heuristic assumptions about locality and causality, Bell established a numerical upper bound on statistical correlations between spatially separated systems and showed that quantum systems could violate it. This upper bound, also known as the Bell or Clauser-Horne-Shimony-Holt (CHSH) i…

[Phys. Rev. A 114, 022208] Published Mon Aug 17, 2026

We investigate the dynamics of two identical spinless fermions on a one-dimensional lattice with open boundary conditions (OBCs), subject to quasiperiodic long-range interactions. Using numerical exact diagonalization (ED), we study this nonintegrable system as a continuous-time quantum walk and unc…

[Phys. Rev. A 114, 022209] Published Mon Aug 17, 2026

Identifying when observed statistics cannot be explained by any reasonable classical model is a central problem in quantum foundations. A principled and universally applicable approach to defining and identifying nonclassicality is given by the notion of generalized noncontextuality. Here, we study …

[Phys. Rev. A 114, 022207] Published Thu Aug 13, 2026

The author demonstrates that quantum objectivity does not scale monotonically with environment size, but instead exists within a certified “two-edge” observer window bounded by record distinguishability and residual dephasing. By identifying local environmental asymmetry as the fundamental resource driving readable records, this study exposes why a bath can efficiently decohere a system while still failing to forge a shared classical reality.

[Phys. Rev. A 114, L020201] Published Thu Aug 13, 2026

We extend the nonlocality transfer matrix framework to quantum phases exhibiting spontaneous translational symmetry breaking. We show that for a broad family of these phases, the standard assumption—wherein the spatial periodicity of the transfer matrix ($u_T$) matches that of the ground state ($u$)—is i…

[Phys. Rev. A 114, 022206] Published Tue Aug 11, 2026

Most studies of quantum batteries have been restricted to conventional atoms whose size is much smaller than the electromagnetic modes. Here we propose a scheme for a quantum battery based on giant atoms in a coupled-resonator waveguide. Specifically, both the charger and the battery are giant atoms…

[Phys. Rev. A 114, 022205] Published Mon Aug 10, 2026

The expressions of the eigenfunctions of the Hawton photon position operator in configuration space are derived for several classes of wave function, including the Riemann-Silberstein and Landau-Peierls cases. Although these eigenfunctions have a simple form in momentum space, the explicit character…

[Phys. Rev. A 114, 022204] Published Thu Aug 06, 2026

We examine a quantum absorption refrigerator that comprises three qubits, each of which is connected with a separate spin-star environment, with the three qubit-bath units coupled through an effective six-body interaction. The refrigerator exhibits the feature of transient cooling, i.e., lowering of…

[Phys. Rev. A 114, 022202] Published Wed Aug 05, 2026

Gaussian boson sampling is an important protocol for testing the performance of photonic quantum simulators. As such, various noise sources have been investigated that degrade the operation of such devices. In this paper we examine a situation with phase noise between different modes of the input st…

[Phys. Rev. A 114, 022203] Published Wed Aug 05, 2026

Recent theoretical studies have predicted the existence of caustics in many-body quantum dynamics, where they manifest as extended regions of enhanced probability density that obey temporal and spatial scaling relations. Focusing on the transverse-field Ising model, we investigate the dynamics initi…

[Phys. Rev. A 114, 022201] Published Tue Aug 04, 2026

Quantum mechanics predicts deviations from exponential decay at short and long times, yet experimental evidence is limited. We report a power-law tail after $\sim 10$ lifetimes in two fluorescent compounds (erythrosine B and eosine Y), confirmed by two detectors probing distinct bands but yielding differe…

[Phys. Rev. A 114, 012218] Published Fri Jul 31, 2026

Elegant Bell inequality is well known for its distinctive property, being maximally violated by maximal entanglement, mutually unbiased bases, and symmetric informationally complete positive operator-valued measure elements. Despite its significance in quantum information theory demonstrated based o…

[Phys. Rev. A 114, 012217] Published Wed Jul 29, 2026

Feedback uses past detection outcomes to dynamically modify a quantum system and is central to quantum control. These outcomes can be stored in a memory, defined as a stochastic function of past measurements. In this work, we investigate the main properties of a general memory function subject to ar…

[Phys. Rev. A 114, 012215] Published Tue Jul 28, 2026

In this work, we consider a general feedback protocol based on quantum-jump detections, where the last detected jump channel is stored in a memory and subsequently used to implement a feedback action, such as modifying the system Hamiltonian conditioned on the last jump. We show that the time evolut…

[Phys. Rev. A 114, 012216] Published Tue Jul 28, 2026

Considering an $N$-level system interacting factorizably with a continuous spectrum, we derive expressions for the bound states and the dynamical evolution within this single-excitation Friedrichs model by using the projection operator formalism. First, we establish explicit criteria to determine the …

[Phys. Rev. A 114, 012214] Published Mon Jul 27, 2026

We establish that the exact quantum dynamics of a Brownian particle in the Caldeira-Leggett model, with at most quadratic external potential, can be mapped, at any temperature, onto a classical, non-Markovian stochastic process in phase space. Starting from a correlated thermal equilibrium state bet…

[Phys. Rev. A 114, 012213] Published Wed Jul 22, 2026

We construct holonomic quantum gates for qubits that are encoded in the near-degenerate vibrational $E$ doublet of a deformable three-body system. Using Kendall's shape theory, we derive the Wilczek-Zee connection that governs adiabatic transport within the $E$ manifold. We show that its restricted holo…

[Phys. Rev. A 114, 012212] Published Mon Jul 20, 2026

Boundary time crystals are a class of exotic dissipative quantum phases that spontaneously break continuous time-translation symmetry in the thermodynamic limit of open quantum systems. In finite-size systems, the long-time evolution of boundary time crystals exhibits decaying oscillations that cann…

[Phys. Rev. A 114, 012211] Published Fri Jul 17, 2026

In the vicinity of a phase transition ergodicity can be broken. Here, different initial many-body configurations evolve toward one of several fixed points, which are macroscopically distinguishable through an order parameter. This mechanism enables state classification in quantum cellular automata a…

[Phys. Rev. A 114, 012209] Published Thu Jul 16, 2026

We investigate the emergence of synchronization blockade arising from the combined action of external driving and internal exchange interactions in quantum oscillators. The external drive indirectly influences the undriven mode through coupling to the driven mode, leading to a breakdown of limit cyc…

[Phys. Rev. A 114, 012210] Published Thu Jul 16, 2026

We consider discrete spacetime models known as quantum walks, which can be used to simulate Dirac particles. In particular, we look at fermion doubling in these models, in which high-momentum states yield additional low-energy solutions which behave like Dirac particles. The presence of doublers car…

[Phys. Rev. A 114, 012208] Published Wed Jul 15, 2026

The equations of time-dependent density functional theory are derived, via the expression for a quantum weak value, from ring polymer self-consistent-field theory using a mathematical correspondence between time and imaginary time. The imaginary-time path-integral formalism of Feynman, in which inve…

[Phys. Rev. A 114, 012206] Published Mon Jul 13, 2026

Non-Hermitian evolution is mathematically invertible, yet finite dynamic range imposes a sharp operational limit on reversibility. We identify precision-induced irreversibility: Amplification, mode mixing (as warranted by non-normality), and a finite resolution floor—whether set by detector noise, e…

[Phys. Rev. A 114, 012207] Published Mon Jul 13, 2026

We consider the motion of a quantum particle whose position is measured in random places at random moments in time. We contrast this motion with the motion of a quantum particle in a potential which varies randomly in space and in time, which could also be thought of as (possibly thermal) noise. We …

[Phys. Rev. A 114, 012205] Published Fri Jul 10, 2026

Spontaneous collapse models provide a possible, testable solution to the quantum measurement problem. While experiments are providing increasingly stronger bounds on their parameters, a full-fledged relativistic extension is still missing. Previous attempts have encountered different obstacles, such…

[Phys. Rev. A 114, 012203] Published Thu Jul 09, 2026

Exploring the shareability and distribution of entanglement possesses fundamental significance in quantum information tasks. In this paper we demonstrate that the square of bipartite entanglement measures $G_q$-concurrence, which is the generalization of concurrence, follows a set of hierarchical monog…

[Phys. Rev. A 114, 012204] Published Thu Jul 09, 2026

Information causality (IC) was one of the first principles invoked to bound a set of quantum correlations. For some families of correlations, this principle recovers exactly the boundary of the quantum set; for others, there is still a gap. We close some of these gaps using a quantifier for IC based…

[Phys. Rev. A 114, 012202] Published Wed Jul 08, 2026

Active matter is characterized by a constant influx and dissipation of energy that gives rise to directed motion. Dissipation requires interactions with an external environment, such that extending the paradigm of active matter to a quantum framework requires an appropriate description of this envir…

[Phys. Rev. A 114, 012201] Published Mon Jul 06, 2026

This Letter considers whether fluctuations of extensive quantities in many-body systems can be consistently monitored, namely, whether measurements can be performed without disturbing future outcome distribution. The answer turns out to be “no” in a large class of situations, and the amount of disturbance can be exactly calculated in terms of linear response quantities.

[Phys. Rev. A 114, L010201] Published Mon Jul 06, 2026

Quantum thermometry aims to measure temperature in nanoscale quantum systems, paralleling classical thermometry. Nonequilibrium quantum thermometry, emerging as a complement to its equilibrium counterpart, addresses scenarios where thermalization is prohibitively slow or real-time temperature monito…

[Phys. Rev. A 113, 062226] Published Tue Jun 30, 2026

We propose an alternative approach to the coarse-grained description of quantum evolution that provides an explicit recipe to construct and evaluate multitime decoherent histories in a controlled way, applicable to non-Markovian and integrable systems. Specifically, we study the local interaction qu…

[Phys. Rev. A 113, 062225] Published Mon Jun 29, 2026

Measurement-only models offer an ideal platform for exploring entanglement dynamics in the absence of unitary evolution. Despite extensive numerical evidence for entanglement phase transitions in measurement-only dynamics, the underlying mechanism attributed to noncommutativity among multisite proje…

[Phys. Rev. A 113, 062223] Published Fri Jun 26, 2026

Typical dynamical quantum chaos probes are initial-state dependent (e.g., local observables or purities) and thus may fail to capture typical decoherent behavior one expects of a subsystem. Quantum channels fully capture the reduced dynamics of a subsystem. Here, we investigate the purity of the Cho…

[Phys. Rev. A 113, 062224] Published Fri Jun 26, 2026

Time-dependent density-functional theory (TDDFT) is a central tool for studying the dynamical electronic structure of molecules and solids, yet aspects of its mathematical foundations remain insufficiently understood. In this work, we revisit the foundations of TDDFT within a finite-dimensional sett…

[Phys. Rev. A 113, 062222] Published Wed Jun 24, 2026

The dynamical generation of quantum resources, such as many-body entanglement, Bell correlations, or spin squeezing, can be achieved via one-axis twisting (OAT) dynamics, which require all-to-all couplings. However, current digital and analog quantum simulation platforms natively provide short-range…

[Phys. Rev. A 113, 062220] Published Tue Jun 23, 2026

We extend Gleason's theorem to the two-dimensional Hilbert space of a qubit by invoking the standard axiom that describes composite quantum systems. The tensor-product structure allows us to derive density matrices and Born's rule for $d=2$ from a simple requirement: the probabilities assigned to meas…

[Phys. Rev. A 113, 062221] Published Tue Jun 23, 2026

If we could shrink the ground-state wave function of a hydrogen atom to a size $R$, at fixed electron mass and charge, the singlet hyperfine attraction in a spin singlet state would scale as $1/R^3$—faster than the increase in kinetic energy—raising the question of why the hyperfine interaction does not …

[Phys. Rev. A 113, 062219] Published Mon Jun 22, 2026

Quantum processes can exhibit scenarios beyond a fixed order of events. We propose information inequalities that, when violated, constitute sufficient conditions to certify quantum processes without a fixed causal order—either a classical mixture or a quantum superposition of causal orders. The ineq…

[Phys. Rev. A 113, 062217] Published Thu Jun 18, 2026

We develop a general theory of Landau-Zener (LZ) tunneling in a two-level system with amplitude-dependent, sign-reversible nonlinear coupling, distinguishing it fundamentally from conventional on-site nonlinearity. Through a combination of analytical and phase-space analysis, we show that beyond a c…

[Phys. Rev. A 113, 062218] Published Thu Jun 18, 2026

A central problem in quantum information is determining quantum-classical boundaries. In the quasiprobability framework, a state is called classical if it is represented by a quasiprobability distribution that is positive, and thus a probability distribution. In recent years, the Kirkwood-Dirac (KD)…

[Phys. Rev. A 113, 062215] Published Tue Jun 16, 2026

A key result in entanglement theory is that the addition of a catalyst dramatically enlarges the set of possible state transformations via local operations and classical communication (LOCC). However, it remains unclear what is the interplay between classical communication and quantum catalysis. Her…

[Phys. Rev. A 113, 062216] Published Tue Jun 16, 2026

It is important to improve the accuracy of quantum measurements and operations both in engineering and fundamental physics. It is known, however, that the achievable accuracy of measurements and unitary operations is generally limited by conservation laws according to the Wigner-Araki-Yanase theorem…

[Phys. Rev. A 113, 062214] Published Mon Jun 15, 2026

Exceptional points are singularities in the spectrum of non-Hermitian systems in which several eigenvectors are linearly dependent and their eigenvalues are equal to each other. Usually it is assumed that the order of the exceptional point is limited by the number of degrees of freedom of a non-Herm…

[Phys. Rev. A 113, 062212] Published Thu Jun 11, 2026

We investigate the two-port scattering process in non-Hermitian dimer models via quantum measurements using external leads. We focus on two exemplary dimer models that preserve parity-time symmetry via spatial gain-loss balance and exhibit nonreciprocity due to directional hopping. The scattering ma…

[Phys. Rev. A 113, 062213] Published Thu Jun 11, 2026

We investigate a nonequilibrium quantum thermometry protocol in which an ensemble of qubits, acting as temperature probes, is weakly coupled to a macroscopic thermal bath. The temperature of the bath, the parameter of interest, is encoded in the dissipator of a Markovian thermalization process. For …

[Phys. Rev. A 113, 062208] Published Tue Jun 09, 2026

We study single-shot distinguishability of locally implementable multipartite unitaries under Local Operations and Classical Communication (LOCC) and global operations. As unitary discrimination depends on both the choice of probing states and the measurements on the evolved states, we classify LOCC…

[Phys. Rev. A 113, 062209] Published Tue Jun 09, 2026

Heisenberg's uncertainty relation is at the origin of understanding minimum uncertainty states and squeezed states of light. In the recent past, the sum uncertainty relation was formulated by Maccone and Pati [L. Maccone and A. K. Pati, Phys. Rev. Lett. 113, 260401 (2014)] and is claimed to be stron…

[Phys. Rev. A 113, 062210] Published Tue Jun 09, 2026

Spontaneous diffusion (i.e., nonconservation of energy) is a prominent, testable prediction of collapse and hybrid classical-quantum gravitational models. Without smearing of the mass density operator, the associated heating (or energy increase) rate diverges, yet the smearing distribution is arbitr…

[Phys. Rev. A 113, 062211] Published Tue Jun 09, 2026

Macroscopic quantum superpositions are widely believed to be unobservable because large systems cannot be perfectly isolated from their environments. Here, we show that even under perfect isolation, intrinsic unitary dynamics in generic many-body systems, as analyzed through the eigenstate thermaliz…

[Phys. Rev. A 113, 062207] Published Mon Jun 08, 2026

Exact quantum master equations serve as a fundamental tool for investigating quantum dissipative dynamics. However, deriving such equations—even when possible—is extremely tedious for multistate and multiatom systems. In this work, we focus exclusively on population dynamics of the extended Jaynes-C…

[Phys. Rev. A 113, 062206] Published Fri Jun 05, 2026

Is entanglement essential for thermal equilibrium? The authors show that multipartite entanglement controls how rapidly fluctuations are suppressed: increasing entanglement produces exponentially strong typicality in small quantum systems, whereas macroscopic equilibrium emerges even without large-scale entanglement.

[Phys. Rev. A 113, L060202] Published Fri Jun 05, 2026

Midcircuit measurements allow the probing of quantum many-body dynamics with spatial and temporal resolution. In this work, the authors discuss how these records can reveal emergent many-body phenomena in space-time.

[Phys. Rev. A 113, L060201] Published Thu Jun 04, 2026

The experimental detection of nonequilibrium quantum criticality remains a challenge, as traditional signatures like dynamical quantum phase transitions rely on hard-to-measure global properties. Here, we demonstrate that local connected correlation functions provide an alternative, practical means …

[Phys. Rev. A 113, 062204] Published Tue Jun 02, 2026

In this work, we compute the out-of-time-ordered correlator (OTOC) for canonical position and momentum operators across a hierarchy of non-Hermitian oscillator models: the exactly solvable Swanson Hamiltonian, its Kerr-nonlinear extension, and parametrically driven variants. By employing the biortho…

[Phys. Rev. A 113, 062205] Published Tue Jun 02, 2026

The spin dynamics of two alkali-metal atoms in an optical tweezer is driven by spin-changing collisions that couple the spin state of the atoms to their relative motion. This paper experimentally studies the resulting spin states when the relative motion is in a thermal state with $k_{B}T$ much larger th…

[Phys. Rev. A 113, 062201] Published Mon Jun 01, 2026

The issue of separating Schrödinger-type quantum time evolution into a product of holonomic and dynamical parts in the nonadiabatic non-Abelian case is examined. We identify all special cases in which this kind of separation is possible, and we prove that separability is a gauge-invariant property o…

[Phys. Rev. A 113, 062202] Published Mon Jun 01, 2026

We investigate the limits of epistemic models in reproducing the empirical predictions of general quantum preparations. This involves comparing the common quantum overlap determined by the antidistinguishability of a set of preparations with the common epistemic overlap of the probability distributi…

[Phys. Rev. A 113, 062203] Published Mon Jun 01, 2026

We propose a formulation of quantum measurement within a modified framework of frames, in which a quantum system—a single qubit—is directly coupled to a classical measurement bit. The qubit is represented as a positive probability distribution over two classical bits, $a$ and $a^{\prime }$, denoted by $p\left(a{a}^{\prime }\right)$. Th…

[Phys. Rev. A 113, 052230] Published Wed May 27, 2026

We study helicity correlations of electron-positron pairs created by a homogeneous time-dependent electric field in the Sauter-Schwinger scenario. Our analysis is based on solving the Dirac equation with Feynman or anti-Feynman boundary conditions, which is equivalent to the scattering matrix approa…

[Phys. Rev. A 113, 052224] Published Tue May 26, 2026

Non-Hermitian operators are now routinely used to describe few-mode systems such as optical resonators and superconducting qubits, and exceptional points (EPs) are defective spectral singularities of such non-Hermitian operators. In contrast, the scattering-theoretic formulation of EP physics for un…

[Phys. Rev. A 113, 052225] Published Tue May 26, 2026

In this work, we propose an efficient quantum-enhanced solid-state photocell based on GaN quantum dots (QDs). We exploit the strong built-in electric field in GaN QDs and the excitonic dipole-dipole interaction between adjacent QDs to break detailed balance, thereby enhancing device performance. Thi…

[Phys. Rev. A 113, 052226] Published Tue May 26, 2026

An approach for analysis of effective interaction between pre- and postselected quantum particles is developed. It is argued that the cases of complete pre- and postselection of particles are more profound than the cases of partial pre- and postselection, since the former goes beyond modification of…

[Phys. Rev. A 113, 052227] Published Tue May 26, 2026

The optical pumping process is a fundamental tool for quantum protocols using the electronic and nuclear spins in the nitrogen-vacancy (NV) center platform. In this work, we explore the process of electronic spin polarization through optical pumping from a thermodynamic perspective. We identify the …

[Phys. Rev. A 113, 052228] Published Tue May 26, 2026

Despite the intrinsic coupling between electric and magnetic fields in random stationary light, their polarization properties are not mutually determined. A complete second-order description thus necessitates a joint electromagnetic treatment. The $6\times 6$ electromagnetic polarization matrix introduced h…

[Phys. Rev. A 113, 052229] Published Tue May 26, 2026

Coupling between quantum and classical systems is consistent, provided the evolution is linear in the state space, preserves the split of systems into quantum and classical degrees of freedom, and preserves probabilities. The evolution law must be a completely positive and norm preserving map. We pr…

[Phys. Rev. A 113, 052223] Published Thu May 21, 2026

In this work, we consider a parameterized Ising model with long-range symmetric pairwise interactions on a network of spin-$1/2$ particles. The system is designed with symmetric dynamics, allowing for the reduction of the state space to a subspace defined by the set of Dicke states. We propose a metho…

[Phys. Rev. A 113, 052222] Published Wed May 20, 2026

The Adler equation is a well-known one-dimensional model describing phase locking and synchronization. Motivated by recent experiments using optomechanical oscillators, we extend this model to include overtone-synthesized sinusoidal coupling with adiabatic temporal modulation. This extension gives r…

[Phys. Rev. A 113, 052220] Published Tue May 19, 2026

Negative states are an intrinsic property of relativistic quantum theory and related to antiparticles in the context of the Dirac sea concept. We show that negative states can dominantly contribute to the diffraction amplitude in the quantum dynamics of the two-photon Kapitza-Dirac effect. We draw o…

[Phys. Rev. A 113, 052221] Published Tue May 19, 2026

A quantum battery is considered as a one-dimensional spin-1/2 chain, which can be described by the $XY$ Heisenberg Hamiltonian. An external magnetic field is applied to charge the quantum battery. The results demonstrate that the counterrotating-wave terms play an important role in the performance of …

[Phys. Rev. A 113, 052216] Published Mon May 18, 2026

We formulate a geometric framework in which physical laws emerge from restricted access to microscopic information. Measurement constraints are modeled as a gauge symmetry acting on density operators, inducing a gauge-reduced space of physically distinguishable states. In the case of quantum thermod…

[Phys. Rev. A 113, 052217] Published Mon May 18, 2026

The study of nonclassicality is essential to understand the quantum-to-classical transition in physical systems. Recently, a witness of nonclassicality has been proposed, linking the ability of a system (the mediator) to create quantum correlations between two quantum probes with its nonclassicality…

[Phys. Rev. A 113, 052218] Published Mon May 18, 2026

Non-Markovian effects are often significant when the system-environment coupling is not weak. Indeed, we find that the non-Markovianity is negligible for a single two-level system undergoing pure dephasing via a weak interaction with a harmonic-oscillator environment. In this paper we show that, wit…

[Phys. Rev. A 113, 052219] Published Mon May 18, 2026

The authors construct Hofstadter Hamiltonians with exactly flat bands whose wave functions can realize the states of any Landau level on the lattice. It opens up a route towards engineering exotic many-body states with ultracold atoms in optical lattices.

[Phys. Rev. A 113, L050201] Published Fri May 15, 2026

Decoherence which describes the disappearance or absence of certain superpositions of quantum states can be employed as an essential tool in diverse quantum technologies. Following this line of thought, we propose a protocol aimed at enhancing the estimation precision of an unknown coupling strength…

[Phys. Rev. A 113, 052214] Published Thu May 14, 2026

We present a manifestly covariant route to designing exact Dirac solutions from geometric data. Given the spinor density $\rho$, four-velocity $v^{\mu }$, spin $s^{\mu }$, Yvon-Takabayashi (YT) angle ${\beta }_s$, and the local Lorentz rotor, covariant relativistic dynamical inversion (CRDI) returns a real four-potential $A_{\mu }$ for w…

[Phys. Rev. A 113, 052215] Published Thu May 14, 2026

Symmetries play a central role in both equilibrium and nonequilibrium phase transitions, yet their quantitative characterization in dynamical quantum phase transitions (DQPTs) remains an open challenge. In this work, we establish a direct connection between the symmetry properties of a many-body mod…

[Phys. Rev. A 113, 052213] Published Wed May 13, 2026

We derive a thermodynamically consistent quantum master equation that satisfies locality for quadratic systems coupled to independent and identical baths at each site. We show that the quasilocal Redfield equation coincides exactly with the Davies equation, which satisfies the detailed balance condi…

[Phys. Rev. A 113, 052212] Published Tue May 12, 2026

We experimentally investigate the dynamics of ergotropy in an open quantum system subject to dissipation by using a linear-optical setup. The total ergotropy, together with its coherent and incoherent components, is extracted at distinct stages of the system's evolution. Our findings reveal that the…

[Phys. Rev. A 113, 052210] Published Mon May 11, 2026

Quantum adiabaticity is the evolution of a quantum system that remains close to an instantaneous eigenstate of a time-dependent Hamiltonian. Using Floquet formalism, we derive a rigorous sufficient condition for adiabaticity in closed, finite-dimensional periodically driven systems that is valid for…

[Phys. Rev. A 113, 052211] Published Mon May 11, 2026

Tying together classical attractor dynamics and dissipative quantum systems, the authors investigate the quantum-to-classical crossover of quasiperiodic attractors, specifically limit tori in coupled Kerr cavities. They identify a universal “quantum melting” process driven by dephasing.

[Phys. Rev. A 113, 052208] Published Fri May 08, 2026