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Quantum electromdynamics in a linear absorbing dielectric medium: The eletromagnetic field in a linear absorptive dielectric medium, is quantized in the framework of the damped polarization model. A Hamiltonian containing a reservoir with continuous degrees of freedom, is proposed. The reservoir minimally interacts wit...
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A better lower bound for quantum algorithms searching an ordered list: We show that any quantum algorithm searching an ordered list of n elements needs to examine at least 1/12 log n-O(1) of them. Classically, log n queries are both necessary and sufficient. This shows that quantum algorithms can achieve only a constan...
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Generating a Schrödinger-cat-like state via a coherent superposition of photonic operations: We propose an optical scheme to generate a superposition of coherent states with enhanced size adopting an interferometric setting at the single-photon level currently available in the laboratory. Our scheme employs a nondege...
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Towards a Multi Target Quantum Computational Logic: Unlike the standard Quantum Computational Logic (QCL), where the carrier of information (target) is conventionally assumed to be only the last qubit over a sequence of many qubits, here we propose an extended version of the QCL (we call Multi Target Quantum Computatio...
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Identification of all Hardy-type correlations for two photons or particles with spin 1/2: By using an alternative, equivalent form of the CHSH inequality and making extensive use of the experimentally testable property of physical locality we determine the 64 different Bell-type inequalities (each one involving four ...
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Experimental implementation of universal holonomic quantum computation on solid-state spins with optimal control: Experimental realization of a universal set of quantum logic gates with high-fidelity is critical to quantum information processing, which is always challenging by inevitable interaction between the quant...
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Calculation of accurate permanent dipole moments of the lowest $^{1,3} Σ^+$ states of heteronuclear alkali dimers using extended basis sets: The obtention of ultracold samples of dipolar molecules is a current challenge which requires an accurate knowledge of their electronic properties to guide the ongoing experimen...
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Quantum Strategies for Rendezvous and Domination Tasks on Graphs with Mobile Agents: This paper explores the application of quantum non-locality, a renowned and unique phenomenon acknowledged as a valuable resource. Focusing on a novel application, we demonstrate its quantum advantage for mobile agents engaged in spe...
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The Generalized Uncertainty Principle: The uncertainty principle lies at the heart of quantum physics, and is widely thought of as a fundamental limit on the measurement precisions of incompatible observables. Here we show that the traditional uncertainty relation in fact belongs to the leading order approximation of a...
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Violation of Bell inequalities through the coincidence-time loophole: The coincidence-time loophole was identified by Larsson & Gill (Europhys. Lett. 67, 707 (2004)); a concrete model that exploits this loophole has recently been described by De Raedt et al. (Found. Phys., to appear). It is emphasized here that De Raed...
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Updating the Born rule: Despite the tremendous empirical success of quantum theory there is still widespread disagreement about what it can tell us about the nature of the world. A central question is whether the theory is about our knowledge of reality, or a direct statement about reality itself. Regardless of their s...
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Fluctuations of Energy-Relaxation Times in Superconducting Qubits: Superconducting qubits are an attractive platform for quantum computing since they have demonstrated high-fidelity quantum gates and extensibility to modest system sizes. Nonetheless, an outstanding challenge is stabilizing their energy-relaxation times...
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Adversarial quantum circuit learning for pure state approximation: Adversarial learning is one of the most successful approaches to modelling high-dimensional probability distributions from data. The quantum computing community has recently begun to generalize this idea and to look for potential applications. In this w...
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Atom-wall dispersive forces from master equation formalism: Using the general expressions for level shifts obtained from the master equation for a small system interacting with a large one considered as a reservoir, we calculate the dispersive potentials between an atom and a wall in the dipole approximation. We analyz...
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Algorithmic cooling for resolving state preparation and measurement errors in quantum computing: State preparation and measurement errors are commonly regarded as indistinguishable. The problem of distinguishing state preparation (SPAM) errors from measurement errors is important to the field of characterizing quantu...
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Entanglement sharing among qudits: Consider a system consisting of n d-dimensional quantum particles (qudits), and suppose that we want to optimize the entanglement between each pair. One can ask the following basic question regarding the sharing of entanglement: what is the largest possible value Emax(n,d) of the mini...
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Quantum-state engineering in cavity magnomechanics formed by two-dimensional magnetic materials: Cavity magnomechanics has become an ideal platform to explore macroscopic quantum effects. Bringing together magnons, phonons, and photons in a system, it opens many opportunities for quantum technologies. It was conventi...
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Macroscopic quantum damping in SQUID rings: The measurement process is introduced in the dynamics of Josephson devices exhibiting quantum behaviour in a macroscopic degree of freedom. The measurement is shown to give rise to a dynamical damping mechanism whose experimental observability could be relevant to understand ...
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String tension and area-law probed using quantum superposition: We propose a method for measuring the string tension in gauge theories, by considering an interference effect of mesons, which is governed by a space-time area law, due to confinement. Although it is only a gedanken experiment for real elementary particles...
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On the Complexity of Quantum Searching Using Complex Queries: We discuss the quantum search algorithm using complex queries that has recently been published by Grover (quant-ph/9706005). We recall the algorithm adding some details showing which complex query has to be evaluated. Based on this version of the algorithm w...
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Programmable quantum emitter formation in silicon: Silicon-based quantum emitters are candidates for large-scale qubit integration due to their single-photon emission properties and potential for spin-photon interfaces with long spin coherence times. Here, we demonstrate local writing and erasing of selected light-emit...
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Relative entropy derivation of the uncertainty principle with quantum side information: We give a simple proof of the uncertainty principle with quantum side information, as in [Berta et al. Nature Physics 6, 659 (2010)], invoking the monotonicity of the relative entropy. Our proof shows that the entropic uncertainty...
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Quantum computation using arrays of N polar molecules in pendular states: We investigate several aspects of realizing quantum computation using entangled polar molecules in pendular states. Quantum algorithms typically start from a product state |00...0> and we show that up to a negligible error, the ground states of p...
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Low-depth simulations of fermionic systems on square-grid quantum hardware: We present a general strategy for mapping fermionic systems to quantum hardware with square qubit connectivity which yields low-depth quantum circuits, counted in the number of native two-qubit fSIM gates. We achieve this by leveraging novel ...
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Generalized Spherical Harmonics: We generalize the spherical harmonics for l=1 and give the differential equation that the generalized forms satisfy. The new forms have an obvious interpretation in the context of quantum mechanics.
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Relativistic Quantum Theory of Cyclotron Resonance in a Medium: In this paper the relativistic quantum theory of cyclotron resonance in an arbitrary medium is presented. The quantum equation of motion for charged particle in the field of plane electromagnetic wave and uniform magnetic field in a medium is solved in the...
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Optimal measurement strategies for the trine states with arbitrary prior probabilities: We investigate the optimal measurement strategy for state discrimination of the trine ensemble of qubit states prepared with arbitrary prior probabilities. Our approach generates the minimum achievable probability of error and als...
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Information theory of quantum systems with some hydrogenic applications: The information-theoretic representation of quantum systems, which complements the familiar energy description of the density-functional and wave-function-based theories, is here discussed. According to it, the internal disorder of the quantum-mec...
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Loophole-free test of local realism via Hardy's violation: Bell's theorem states that quantum mechanical description on physical quantity cannot be fully explained by local realistic theories, and lays solid basis for various quantum information applications. Hardy's paradox is celebrated to be the simplest form of Bel...
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Non-Perturbative Renormalization Group Analysis of the Ohmic Quantum Dissipation: We analyze quantum tunneling with the Ohmic dissipation by the non-perturbative renormalization group method. We calculate the localization susceptibility to evaluate the critical dissipation for the quantum-classical transition, and fi...
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Efimov Physics: a review: This article reviews theoretical and experimental advances in Efimov physics, an array of quantum few-body and many-body phenomena arising for particles interacting via short-range resonant interactions, that is based on the appearance of a scale-invariant three-body attraction theoretically d...
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Measurements with prediction and retrodiction on the collective spin of 10^{11} atoms beat the standard quantum limit: Quantum probes using $N$ uncorrelated particles give a limit on the measurement sensitivity referred to as the standard quantum limit (SQL). The SQL, however, can be overcome by exploiting quantum en...
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Quantum Interference, Hidden Symmetries: Theory and Experimental Facts: The concept of quantum superposition is reconsidered and discussed from the viewpoint of Bohmian mechanics, the hydrodynamic formulation of quantum mechanics, in order to elucidate some physical consequences that go beyond the simple mathematical i...
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All Optical Quantum Teleportation: We propose an all optical, continuous variable, quantum teleportation scheme based on optical parametric amplifiers.
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Quantum probing topological phase transitions by non-Markovianity: Understanding the physical significance and probing the global invariants characterizing quantum topological phases in extended systems is a main challenge in modern physics with major impact in different areas of science. Here, a quantum-information-in...
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Intertwining of exactly solvable generalized Schrodinger equations: The Darboux transformation operator technique in differential and integral forms is applied to the generalized Schrodinger equation with a position-dependent effective mass and with linearly energy-dependent potentials. Intertwining operators are obtai...
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Quantum Mechanical Heat Transport in Disordered Harmonic Chains: We investigate the mechanism of heat conduction in ordered and disordered harmonic onedimensional chains within the quantum mechanical Langevin method. In the case of the disordered chains we find indications for normal heat conduction which means that th...
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Controlling a d-level atom in a cavity: In this paper we study controllability of a $d$-level atom interacting with the electromagnetic field in a cavity. The system is modelled by an ordered graph $\Gamma$. The vertices of $\Gamma$ describe the energy levels and the edges allowed transitions. To each edge of $\Gamma$ ...
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Multi-mode quantum correlation generated from an unbalanced SU(1,1) interferometer using ultra-short laser pulses as pump: Multi-mode entanglement is one of the critical resource in quantum information technology. Generating large scale multi-mode entanglement state by coherently combining time-delayed continuous var...
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Implications of Electronics Constraints for Solid-State Quantum Error Correction and Quantum Circuit Failure Probability: In this paper we present the impact of classical electronics constraints on a solid-state quantum dot logical qubit architecture. Constraints due to routing density, bandwidth allocation, signal t...
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Exact solutions for a universal set of quantum gates on a family of iso-spectral spin chains: We find exact solutions for a universal set of quantum gates on a scalable candidate for quantum computers, namely an array of two level systems. The gates are constructed by a combination of dynamical and geometrical (non-A...
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Interferometric Tests of Teleportation: We investigate a direct test of teleportation efficacy based on a Mach-Zehnder interferometer. The analysis is performed for continuous variable teleportation of both discrete and continuous observables.
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The scaling of boson sampling experiments: Boson sampling is the problem of generating a quantum bit stream whose average is the permanent of a $n\times n$ matrix. The bitstream is created as the output of a prototype quantum computing device with $n$ input photons. It is a fundamental challenge to verify boson samplin...
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A high fidelity heralded squeezing gate: A universal squeezing gate capable of squeezing arbitrary input states is essential for continuous-variable quantum computation~\cite{PRA79062318,PRL112120504}. However, in present state-of-the-art techniques~\cite{PRA90060302,PRL106240504}, the fidelity of such gates is ultimat...
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Field-gradient measurement using a Stern-Gerlach atomic interferometer with butterfly geometry: Atomic interferometers have been studied as a promising device for precise sensing of external fields. Among various configurations, a particular configuration with a butterfly-shaped geometry has been designed to sensitiv...
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A comment on the paper "How can a Result of a Single Coin Toss Turn Out to be 100 Heads" by C. Ferrie and J. Combes: The authors of a recent paper [Phys. Rev. Lett. 113, 120404 (2014)] suggest that "weak values are not inherently quantum but rather a purely statistical feature of pre- and postselection with disturban...
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Out-of-time-order correlators and quantum phase transitions in the Rabi and Dicke model: The out-of-time-order correlators (OTOCs) is used to study the quantum phase transitions (QPTs) between the normal phase and the superradiant phase in the Rabi and few-body Dicke models with large frequency ratio of theatomic lev...
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Anomalous Decay and Decoherence in Atomic Gases: Pair collisions in atomic gases lead to decoherence and decay. Assuming that all the atoms in the gas are equally likely to collide one is led to consider Lindbladian of mean field type where the evolution in the limit of many atoms reduces to a single qudit Lindbladian ...
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An Introduction to Superconducting Qubits and Circuit Quantum Electrodynamics: A subset of the concepts of circuit quantum electrodynamics are reviewed as a reference to the Axion Dark Matter Experiment (ADMX) community as part of the proceedings of the 2nd Workshop on Microwave Cavities and Detectors for Axion Resea...
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Quantum correlation in three-qubit Heisenberg model with Dzyaloshinskii-Moriya interaction: We investigate the pairwise thermal quantum discord in a three-qubit XXZ model with Dzyaloshinskii-Moriya (DM) interaction. We find that the DM interaction can increase quantum discord to a fixed value in the anti- ferromagnet...
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Resolving non-perturbative renormalization of a microwave-dressed weakly anharmonic superconducting qubit: Microwave driving is a ubiquitous technique for superconducting qubits (SCQs), but the dressed states description based on the conventionally used perturbation theory cannot fully capture the dynamics in the str...
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Optical switching and inversionless amplification controlled by state-dependent alignment of molecules: Switching anisotropic molecules from strongly-absorbing to strongly-amplifying through a transparent state is shown to be possible by application of dc or ac control electric fields without the requirement of the p...
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Modeling near ground-state cooling of two-dimensional ion crystals in a Penning trap using electromagnetically induced transparency: Penning traps, with their ability to control planar crystals of tens to hundreds of ions, are versatile quantum simulators. Thermal occupations of the motional drumhead modes, transvers...
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Dissipative many-body physics of cold Rydberg atoms: In the last twenty years, Rydberg atoms have become a versatile and much studied system for implementing quantum many-body systems in the framework of quantum computation and quantum simulation. However, even in the absence of coherent evolution Rydberg systems exhib...
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Resource Reduction in Multiplexed High-Dimensional Quantum Reed-Solomon Codes: Quantum communication technologies will play an important role in quantum information processing in the near future as we network devices together. However, their implementation is still a challenging task due to both loss and gate errors....
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Supermeasured: Violating Bell-Statistical Independence without violating physical statistical independence: Bell's theorem is often said to imply that quantum mechanics violates local causality, and that local causality cannot be restored with a hidden-variables theory. This however is only correct if the hidden-vari...
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A New Strategy of Quantum-State Estimation for Achieving the Cramer-Rao Bound: We experimentally analyzed the statistical errors in quantum-state estimation and examined whether their lower bound, which is derived from the Cramer-Rao inequality, can be truly attained or not. In the experiments, polarization states of...
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Analysis of the SGA method for obtaining energy spectra: We analyze and clarify how the SGA (spectrum generating algebra) method has been applied to different potentials. We emphasize that each energy level $E_\nu$ obtained originally by Morse belongs to a {\em different} ${\mathfrak {so}}(2,1)$ multiplet. The correspo...
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Accurate and Efficient Quantum Computations of Molecular Properties Using Daubechies Wavelet Molecular Orbitals: A Benchmark Study against Experimental Data: Although quantum computation (QC) is regarded as a promising numerical method for computational quantum chemistry, current applications of quantum-chemistry c...
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Quantum correlations which imply causation: In ordinary, non-relativistic, quantum physics, time enters only as a parameter and not as an observable: a state of a physical system is specified at a given time and then evolved according to the prescribed dynamics. While the state can, and usually does, extend across all ...
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Driving Atoms Into Decoherence-Free States: We describe the decoherence-free subspace of N atoms in a cavity, in which decoherence due to the leakage of photons through the cavity mirrors is suppressed. We show how the states of the subspace can be entangled with the help of weak laser pulses, using the high decay rate...
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Decomposition of bipartite and multipartite unitary gates into the product of controlled unitary gates: We show that any unitary operator on the $d_A\times d_B$ system ($d_A\ge 2$) can be decomposed into the product of at most $4d_A-5$ controlled unitary operators. The number can be reduced to $2d_A-1$ when $d_A$ is ...
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Bell's inequality violation for entangled generalized Bernoulli states in two spatially separate cavities: We consider the entanglement of orthogonal generalized Bernoulli states in two separate single-mode high-$Q$ cavities. The expectation values and the correlations of the electric field in the cavities are obtain...
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Indistinguishable Encoding for Bidirectional Quantum Key Distribution: Theory to Experiment: We present for the first time, a bidirectional Quantum Key Distribution protocol with minimal encoding operations derived from the use of two `nonorthogonal' unitary transformations selected from two mutually unbiased unitary...
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Control of spontaneous emission of qubits from weak to strong coupling: Photon emission and absorption by an individual qubit are essential elements for the quantum manipulation of light. Here we demonstrate the controllability of spontaneous emission of a qubit in various electromagnetic environments. The parameter re...
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Adiabatic Product Expansion: The time-evolution operator for an explicitly time-dependent Hamiltonian is expressed as the product of a sequence of unitary operators. These are obtained by successive time-dependent unitary transformations of the Hilbert space followed by the adiabatic approximation at each step. The res...
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Spin-echo entanglement protection from random telegraph noise: We analyze local spin-echo procedures to protect entanglement between two non-interacting qubits, each subject to pure-dephasing random telegraph noise. For superconducting qubits this simple model captures characteristic features of the effect of bistable ...
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Effect of Decoherence for Gate Operations on a Superconducting Bosonic Qubit: High-quality-factor 3D cavities in superconducting circuits are ideal candidates for bosonic logical qubits as their fidelity is limited only by the low photon loss rate. However, the transmon qubits that are used to manipulate bosonic qubi...
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Sub-Attosecond Metrology via X-Ray Hong-Ou-Mandel Effect: We show that sub-attosecond delays and sub-Angstrom optical path differences can be measured by using Hong-Ou-Mandel interference measurements with x-rays. We propose to use a system comprising a source based on spontaneous parametric down-conversion for the gen...
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Quantum control of "quantum triple collisions" in a maximally symmetric three-body Coulomb problem: In Coulomb 3-body problems, configurations of close proximity of the particles are classically unstable. In confined systems they might however exist as excited quantum states. Quantum control of such states by time ch...
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Stabilization of nonclassical states of one- and two-mode radiation fields by reservoir engineering: We analyze a quantum reservoir engineering method, originally introduced by [Sarlette et al. in Phys. Rev. Lett. 107, 010402 (2011) -- arXiv 1011.5057], for the stabilization of non-classical field states in high qual...
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Magnetic-field-learning using a single electronic spin in diamond with one-photon-readout at room temperature: Nitrogen-vacancy (NV) centres in diamond are appealing nano-scale quantum sensors for temperature, strain, electric fields and, most notably, for magnetic fields. However, the cryogenic temperatures required...
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Temperature-Controlled Entangled-Photon Absorption Spectroscopy: Entangled two-photon absorption spectroscopy (TPA) has been widely recognized as a powerful tool for revealing relevant information about the structure of complex molecular systems. However, to date, the experimental implementation of this technique has r...
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Uncertainty relation between detection probability and energy fluctuations: A classical random walker starting on a node of a finite graph will always reach any other node since the search is ergodic, namely it is fully exploring space, hence the arrival probability is unity. For quantum walks, destructive interferen...
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Single-atom single-photon coupling facilitated by atomic-ensemble dark-state mechanisms: We propose to couple single atomic qubits to photons incident on a cavity containing an atomic ensemble of a different species that mediates the coupling via Rydberg interactions. Subject to a classical field and the cavity field...
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Remote two-qubit state creation and its robustness: We consider the problem of remote two-qubit state creation using the two-qubit excitation pure initial state of the sender. The communication line is based on the optimized boundary controlled chain with two pairs of properly adjusted coupling constants. The creation ...
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How Much Structure Is Needed for Huge Quantum Speedups?: I survey, for a general scientific audience, three decades of research into which sorts of problems admit exponential speedups via quantum computers -- from the classics (like the algorithms of Simon and Shor), to the breakthrough of Yamakawa and Zhandry from Apr...
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Cannikin's Law in Tensor Modeling: A Rank Study for Entanglement and Separability in Tensor Complexity and Model Capacity: This study clarifies the proper criteria to assess the modeling capacity of a general tensor model. The work analyze the problem based on the study of tensor ranks, which is not a well-defined qu...
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Non-Markovian waiting time distribution: Simulation methods based on stochastic realizations of state vector evolutions are commonly used tools to solve open quantum system dynamics, both in the Markovian and non-Markovian regime. Here, we address the question of waiting time distribution (WTD) of quantum jumps for non...
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Generation of NPT Entanglement from Nonclassical Photon Statistics: With a product state of the form $\rho_{in} = \rho_a\otimes|0>_b_b< 0|$ as input, the output two-mode state $\rho_{{\rm out}}$, of the beam splitter is shown to be NPT whenever the photon number distribution (PND) statistics $\{p(n_a) \}$ associated wi...
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Nonlocality at detection and conservation of energy. Was Einstein looking for an "epistemic" interpretation, a "superdeterministic" one, or both?: In the Solvay conference (1927) Einstein argued against the quantum nonlocal decision at detection on the basis of a simple single-particle experiment, but thereafter he...
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Low-depth Gaussian State Energy Estimation: Recent progress in quantum computing is paving the way for the realization of early fault-tolerant quantum computers. To maximize the utility of these devices, it is important to develop quantum algorithms that match their capabilities and limitations. Motivated by this, rece...
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Quantum Blackjack or Can MIT Bring Down the House Again?: We examine the advantages that quantum strategies afford in communication-limited games. Inspired by the card game blackjack, we focus on cooperative, two-party sequential games in which a single classical bit of communication is allowed from the player who move...
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Entanglement evolution in a cascaded system with losses: The dynamics of a cascaded system that consists of two atom-cavity subsystems is studied by using the quantum trajectory method. Unwanted losses are included, such as photon absorption and scattering by the cavity mirrors and spontaneous emission of the atoms. Co...
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Routing quantum information in spin chains: Two different models for performing efficiently routing of a quantum state are presented. Both cases involve an XX spin chain working as data bus and additional spins that play the role of sender and receivers, one of which is selected to be the target of the quantum state tr...
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Non-isospectrality of the generalized Swanson Hamiltonian and harmonic oscillator: The generalized Swanson Hamiltonian $H_{GS} = w (\tilde{a}\tilde{a}^\dag+ 1/2) + \alpha \tilde{a}^2 + \beta \tilde{a}^{\dag^2}$ with $\tilde{a} = A(x)d/dx + B(x)$, can be transformed into an equivalent Hermitian Hamiltonian with the he...
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Efficient Coherent Control by Optimized Sequences of Pulses of Finite Duration: Reliable long-time storage of arbitrary quantum states is a key element for quantum information processing. In order to dynamically decouple a spin or quantum bit from a dephasing environment, we introduce an optimized sequence of $N$ con...
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Entanglement of distant optomechanical systems: We theoretically investigate the possibility to generate non-classical states of optical and mechanical modes of optical cavities, distant from each other. A setup comprised of two identical cavities, each with one fixed and one movable mirror and coupled by an optical fi...
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Pump-efficient Josephson parametric amplifiers with high saturation power: Circuit QED based quantum information processing relies on low noise amplification for signal readout. In the realm of microwave superconducting circuits, this amplification is often achieved via Josephson parametric amplifiers (JPA). In the p...
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Pre-Born-Oppenheimer Dirac-Coulomb-Breit computations for two-body systems: The sixteen-component, no-pair Dirac--Coulomb--Breit equation, derived from the Bethe--Salpeter equation, is solved in a variational procedure using Gaussian-type basis functions for the example of positronium, muonium, hydrogen atom, and muo...
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A Non-Local Reality: Is there a Phase Uncertainty in Quantum Mechanics?: A century after the advent of Quantum Mechanics and General Relativity, both theories enjoy incredible empirical success, constituting the cornerstones of modern physics. Yet, paradoxically, they suffer from deep-rooted, so-far intractable, confli...
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Activated and non activated dephasing demonstrated in NV center dynamics: We analyze different decoherence processes in a system coupled to a bath. Apart from the well known standard dephasing mechanism which is temperature dependent an alternative mechanism is presented, the spin-swap dephasing which does not need ini...
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Topological lattices realized in superconducting circuit optomechanics: Cavity optomechanics enables controlling mechanical motion via radiation pressure interaction, and has contributed to the quantum control of engineered mechanical systems ranging from kg scale LIGO mirrors to nano-mechanical systems, enabling groun...
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Internal entanglement and external correlations of any form limit each other: We show a relation between entanglement and correlations of any form. The internal entanglement of a bipartite system, and its correlations with another system, limit each other. A measure of correlations, of any nature, cannot increase und...
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Classical and quantum chaos in a three-mode bosonic system: We study the dynamics of a three-mode bosonic system with mode-changing interactions. For large mode occupations the short-time dynamics is well described by classical mean-field equations allowing us to study chaotic dynamics in the classical system and its s...
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Theory of atomic diffraction from evanescent waves: We review recent theoretical models and experiments dealing with the diffraction of neutral atoms from a reflection grating, formed by a standing evanescent wave. We analyze diffraction mechanisms proposed for normal and grazing incidence, point out their scopes and c...
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Generalized distillability conjecture and generalizations of Cauchy-Bunyakovsky-Schwarz inequality and Lagrange identity: Let rho_k, k=1,2,...,m, be the critical Werner state in a bipartite d_k by d_k quantum system, i.e., the one that separates the 1-distillable Werner states from those that are 1-indistillable. We ...
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Nonadditive entropy for random quantum spin-S chains: We investigate the scaling of Tsallis entropy in disordered quantum spin-S chains. We show that an extensive scaling occurs for specific values of the entropic index. Those values depend only on the magnitude S of the spins, being directly related with the effective...
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Boltzmann machines as thermal models for quantum systems: We successfully model the behavior of two-spin systems using neural networks known as conditional Restricted Boltzmann Machines (cRBMs) which encode physical information in the properties of a thermal ensemble akin to an Ising model. The result gives local "hidd...
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Bohmian transmission and reflection dwell times without trajectory sampling: Within the framework of Bohmian mechanics dwell times find a straightforward formulation. The computation of associated probabilities and distributions however needs the explicit knowledge of a relevant sample of trajectories and therefore i...
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