Latest in quant-ph

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Measuring Electromagnetic and Gravitational Responses of Photonic Landau LevelsFeb 13 2018The topology of an object describes global properties that are insensitive to local perturbations. Classic examples include string knots and the genus (number of handles) of a surface: no manipulation of a closed string short of cutting it changes its ... More
Topological PhotonicsFeb 12 2018Topological photonics is a rapidly-emerging field of research in which geometrical and topological ideas are exploited to design and control the behavior of light. Drawing inspiration from the discovery of the quantum Hall effects and topological insulators ... More
Electron Spin Coherences in Rare-Earth Optically Excited States for Microwave to Optical Quantum TransducersFeb 09 2018Efficient and reversible optical to microwave coherent transducers are required to enable entanglement transfer between superconducting qubits and light for quantum networks. Rare-earth-doped crystals that possess narrow optical and spin transitions are ... More
Non-Markovian quantum control as coherent stochastic trajectoriesFeb 09 2018Feb 12 2018We develop a notion of stochastic quantum trajectories. First, we construct a basis set of trajectories, called elementary trajectories, and go on to show that any quantum dynamical process, including those that are non-Markovian, can be expressed as ... More
Topological indexes in symmetry preserving dynamicsFeb 08 2018The quench dynamics of topological phases have received intensive investigations in recent years. In this work, we prove exactly that the topological invariants for both $\mathbb{Z}$ and $\mathbb{Z}_2$ indexes are independent of time in symmetry preserving ... More
Phase estimation with squeezed single photonsFeb 08 2018We address the performance of an interferometric setup in which a squeezed single photon interferes at a beam splitter with a coherent state. Our analysis in based on both the quantum Fisher information and the sensitivity when a Mach-Zehnder setup is ... More
Coherent control of solid state nuclear spin nano-ensemblesFeb 08 2018Detecting and controlling nuclear spin nano-ensembles is crucial for the further development of nuclear magnetic resonance (NMR) spectroscopy and for the emerging solid state quantum technology. Here we present the fabrication of a $\approx$ 1 nanometre ... More
Roughness as Classicality Indicator of a Quantum StateFeb 08 2018We define a new quantifier of classicality for a quantum state, the Roughness, which is given by the $\mathcal{L}^2 (\R^2)$ distance between Wigner and Husimi functions. We show that the Roughness is bounded and therefore it is a useful tool for comparison ... More
Frequency-encoded linear cluster states with coherent Raman photonsFeb 08 2018Entangled multi-qubit states are an essential resource for quantum information and computation. Solid-state emitters can mediate interactions between subsequently emitted photons via their spin, thus offering a route towards generating entangled multi-photon ... More
Multi-state and multi-hypothesis discrimination with open quantum systemsFeb 08 2018We show how an upper bound for the ability to discriminate any number N of candidates for the Hamiltonian governing the evolution of an open quantum system may be calculated by numerically efficient means. Our method applies an effective master equation ... More
Classical evolution of quantum systemsFeb 08 2018For studying quantum phenomena in time, it is vital to have a profound understanding of the classical dynamics. For this reason, we derive equations of motions describing the classical propagation of a quantum system. A comparison of this classical evolution ... More
Dynamical protection of nonclassical correlation in a quantum algorithmFeb 08 2018A quantum memory interacts with its environment and loses information via decoherence as well as incoherence. A robust quantum control that prepares, preserves, and manipulates nonclassical correlations even in the presence of environmental influence ... More
The Multiphoton Boson Sampling Machine Doesn't Beat Early Classical Computers for Five-boson SamplingFeb 08 2018An ignored algorithm called Store-reuse for calculating the permanent of an n * n matrix is considered. It utilizes computer storages sufficiently, and uses stored data repetitively. The analysis manifests that the numbers of multiplications and additions ... More
Composable security analysis of continuous-variable measurement-device-independent quantum key distribution against coherent attacksFeb 08 2018Measurement-device-independent quantum key distribution protocol, whose security analysis does not rely on any assumption on the detection system, can immune all the detection attacks. We give a first composable security analysis for continuous-variable ... More
Entanglement Verification, with or without tomographyFeb 07 2018Multipartite entanglement has been widely regarded as key resources in distributed quantum computing, for instance, multi-party cryptography, measurement based quantum computing, quantum algorithms. It also plays a fundamental role in quantum phase transitions, ... More
Multipartite entanglement in spin chains and the HyperdeterminantFeb 07 2018A way to characterize multipartite entanglement in pure states of a spin chain with $n$ sites and local dimension $d$ is by means of the Cayley hyperdeterminant. The latter quantity is a polynomial constructed with the components of the wave function ... More
Detecting false correlations: Uncovering a faked Bell-inequality violationFeb 07 2018It is possible for two parties, Alice and Bob, to establish a secure communication link by sharing an ensemble of entangled particles, and then using these particles to generate a secret key. One way to establish that the particles are indeed entangled ... More
The revolution in physics of the early Nineteenth century revisited in the context of science-and-society interactionFeb 07 2018The radical changes in the concepts and approach in Physics at the turn of the Nineteenth century were so deep, that is acknowledged as a revolution. However, in 1970 Thomas Kuhn's careful reconstruction of the researches on the black body problem, the ... More
Quasi-exactly solvable Schrödinger equations, symmetric polynomials, and functional Bethe ansatz methodFeb 07 2018For applications to quasi-exactly solvable Schr\"odinger equations in quantum mechanics, we consider the general conditions that have to be satisfied by the coefficients of a second-order differential equation with at most $k+1$ singular points in order ... More
Management of the Correlations of Ultracold Bosons in Triple WellsFeb 07 2018Ultracold interacting atoms are an excellent tool to study correlation functions of many-body systems that are generally eluding detection and manipulation. Herein, we investigate the ground state of bosons in a tilted triple-well potential and characterize ... More
Monogamy of particle statistics in tripartite systems simulating bosons and fermionsFeb 07 2018In the quantum world correlations can take form of entanglement which is known to be monogamous. In this work we show that another type of correlations, indistinguishability, is also restricted by some form of monogamy. Namely, if particles A and B simulate ... More
Reply to comment in arXiv:1802.01382Feb 07 2018Here we respond to a comment [arXiv:1802.01382] submitted recently on 'Experimental Verification of a Jarzynski-Related Information-Theoretic Equality by a Single Trapped Ion' PRL 120 010601 (2018).
Double-passage ground-state cooling induced by quantum interference in the hybrid optomechanical systemFeb 07 2018We propose a quantum interference cooling scheme for a nano-mechanical resonator (NAMR) in a hybrid optomechanical system, where the atoms are trapped in an optomechanical cavity, coupling to an additional optical cavity. The absorption of the optomechanical ... More
A Schematic Definition of Quantum Polynomial Time ComputabilityFeb 07 2018In the past four decades, the notion of quantum polynomial-time computability has been realized by the theoretical models of quantum Turing machines and quantum circuits. Here, we seek a third model, which is a quantum analogue of the schematic (inductive ... More
Quantum-optimal detection of one-versus-two incoherent optical sources with arbitrary separationFeb 07 2018We analyze the fundamental quantum limit of the resolution of an optical imaging system from the perspective of the detection problem of deciding whether the optical field in the image plane is generated by one incoherent on-axis source with brightness ... More
Universal Approach to Quantum Adiabaticity via Ancilla CavityFeb 07 2018A central challenge in the successful implementation of adiabatic quantum algorithms is to maintain the quantum adiabaticity during the entire evolution. However, the energy gap between the ground and the excited states of interacting many-body systems ... More
Unitarity and Universality in non relativistic Conformal Field theoryFeb 06 2018We relate the notion of unitarity of a $SL(2,\mathbf{R})$ invariant field theory with that of a Schr\"odinger field theory using the fact that $SL(2,\mathbf{R})$ is a subgroup of Schr\"odinger group. Exploiting $SL(2,\mathbf{R})$ unitarity, we derive ... More
Reconfigurable topological phases in next-nearest-neighbor coupled resonator latticesFeb 06 2018We present a reconfigurable topological photonic system consisting of a 2D lattice of coupled ring resonators, with two sublattices of site rings coupled by link rings, which can be accurately described by a tight-binding model. Unlike previous coupled-ring ... More
Topological phase transition measured in a dissipative metamaterialFeb 06 2018We construct a metamaterial from radio-frequency harmonic oscillators, and find two topologically distinct phases resulting from dissipation engineered into the system. These phases are distinguished by a quantized value of bulk energy transport. The ... More
Fragile aspects of topological transition in lossy and parity-time symmetric quantum walksFeb 06 2018Quantum walks often provide telling insights about the structure of the system on which they are performed. In PT-symmetric and lossy dimer lattices, the topological properties of the band structure manifest themselves in the quantization of the mean ... More
Velocimetry of cold atoms by matterwave interferometryFeb 06 2018We present a method for the velocimetry of cold atoms by matterwave interferometry, which we have used to measure the velocity distributions within freely-expanding clouds of $^{85}$Rb atoms at temperatures of 17 and 33 $\mu$K. Quadrature measurement ... More
Black Holes and Complexity ClassesFeb 06 2018It is not known what the limitations are on using quantum computation to speed up classical computation. An example would be the power to speed up PSPACE-complete computations. It is also not known what the limitations are on the duration of time over ... More
Certifying the building blocks of quantum computers from Bell's theoremFeb 06 2018The power of quantum computers relies on the capability of their components to maintain faithfully and process accurately quantum information. Since this property eludes classical certification methods, fundamentally new protocols are required to guarantee ... More
The ultimate precision of quantum illuminationFeb 06 2018Quantum illumination is a technique for detecting the presence of a target in a noisy environment by means of a quantum probe. We prove that the two-mode squeezed vacuum state is the optimal probe for quantum illumination in the scenario of asymmetric ... More
Tunable current circulation in triangular quantum-dot metastructuresFeb 06 2018Advances in fabrication and control of quantum dots allow the realization of metastructures that may exhibit novel electrical transport phenomena. Here, we investigate the electrical current passing through one such metastructure, a system composed of ... More
Exact local correlations and full counting statistics for arbitrary states of the one-dimensional interacting Bose gasFeb 06 2018We derive exact analytic expressions for the $n$-body local correlations in the one-dimensional Bose gas with contact repulsive interactions (Lieb-Liniger model) in the thermodynamic limit. Our results are valid for arbitrary states of the model, including ... More
Observation of the topological Anderson insulator in disordered atomic wiresFeb 06 2018Topology and disorder have deep connections and a rich combined influence on quantum transport. In order to probe these connections, we synthesized one-dimensional chiral symmetric wires with controllable disorder via spectroscopic Hamiltonian engineering, ... More
Hyperspherical-LOCV Approximation to Resonant BECFeb 06 2018We study the ground state properties of a system of $N$ harmonically trapped bosons of mass $m$ interacting with two-body contact interactions, from small to large scattering lengths. This is accomplished in a hyperspherical coordinate system that is ... More
Causal Classical Physics in Time Symmetric Quantum MechanicsFeb 06 2018The letter submitted is an executive summary of our previous paper. To solve the Einstein Podolsky Rosen 'paradox' the two boundary quantum mechanics is taken as self consistent interpretation of quantum dynamics. The difficulty with this interpretation ... More
Control of fluctuations and heavy tails for heat variation in the two-time measurement frameworkFeb 06 2018We study heat fluctuations in the two-time measurement framework. For bounded perturbations, we give sufficient ultraviolet regularity conditions on the perturbation for the moments of the heat variation to be uniformly bounded in time, and for the Fourier ... More
Of Local Operations and Physical WiresFeb 06 2018In this work (multipartite) entanglement, discord and coherence are unified as different aspects of a single underlying resource theory defined through simple and operationally meaningful elemental operations. This is achieved by revisiting the resource ... More
Effects of interaction imbalance in a strongly repulsive one-dimensional Bose gasFeb 06 2018We calculate the spatial distributions and the dynamics of a few-body two-component strongly interacting Bose gas confined to an effectively one-dimensional trapping potential. We describe the densities for each component in the trap for different interaction ... More
Probing the Interface of a Phase-Separated State in a Repulsive Bose-Fermi MixtureFeb 06 2018We probe the interface between a phase-separated Bose-Fermi mixture consisting of a small BEC of $^{41}$K residing in a large Fermi sea of $^6$Li. We quantify the residual spatial overlap between the two components by measuring three-body recombination ... More
Manipulation of two quantum systems through their mutual interaction in presence of a radiation fieldFeb 06 2018In cavity QED, the mutual interaction between natural atomic systems in presence of a radiation field was ignored due to its negligible impact compared with the coupling to the field. The newly engineered artificial atomic systems (such as quantum dots ... More
Hyper- and hybrid nonlocalityFeb 06 2018The controlled generation and identification of quantum correlations, usually encoded in either qubits or continuous degrees of freedom, builds the foundation of quantum information science. Recently, more sophisticated approaches, involving a combination ... More
Programming infinite machinesFeb 06 2018For infinite machines which are free from the classical Thompson's lamp paradox we show that they are not free from its inverted version. We provide a program for infinite machines and an infinite mechanism which simulate this paradox. While their finite ... More
Stochasticity and Bell-type Quantum Field TheoryFeb 06 2018This paper critically discusses an objection proposed by H. Nikolic against the naturalness of the stochastic dynamics implemented by the Bell-type Quantum Field Theory, an extension of Bohmian Mechanics able to describe the phenomena of particles creation ... More
A distinguishable single excited-impurity in a Bose-Einstein condensateFeb 06 2018We investigate the properties of a distinguishable single excited state impurity pinned in the center of a trapped Bose-Einstein condensate (BEC) in a one-dimensional harmonic trapping potential by changing the bare mass of the impurity and its interspecies ... More
Bright squeezed vacuum in a nonlinear interferometer: frequency/temporal Schmidt-mode descriptionFeb 06 2018Control over the spectral properties of the bright squeezed vacuum (BSV), a highly multimode non-classical macroscopic state of light that can be generated through high-gain parametric down conversion, is crucial for many applications. In particular, ... More
Quantum First Passage Time Problem-A Bohmian PerspectiveFeb 06 2018The prediction of arrival time or first passage time statistics of a quantum particle is an open problem, which challenges the foundations of quantum theory. One of the most promising and insightful approaches to this problem stems from the de Broglie-Bohm ... More
Circuit Quantum Electrodynamics of Granular Aluminum ResonatorsFeb 06 2018Feb 07 2018The introduction of crystalline defects or dopants can give rise to so-called "dirty superconductors", characterized by reduced coherence length and quasiparticle mean free path. In particular, granular superconductors such as Granular Aluminum (GrAl), ... More
Blow-up profile of rotating 2D focusing Bose gasesFeb 06 2018We consider the Gross-Pitaevskii equation describing an attractive Bose gas trapped to a quasi 2D layer by means of a purely harmonic potential, and which rotates at a fixed speed of rotation $\Omega$. First we study the behavior of the ground state when ... More
Analog quantum simulation of generalized Dicke models in trapped ionsFeb 06 2018We propose the analog quantum simulation of generalized Dicke models in trapped ions. By combining bicromatic laser interactions on multiple ions we can generate all regimes of light-matter coupling in these models, where here the light mode is mimicked ... More
Breakdown of Ehrenfest theorem for free particle constrained on a hypersurfaceFeb 06 2018There is a belief that the Ehrenfest theorem holds true universally. We demonstrate that for a classically nonrelativistic particle constrained on an $N-1$ ($N\geq 2$) curved hypersurface embedded in $N$ flat space, the theorem breaks down.
Renormalization for a Scalar Field in an External Scalar PotentialFeb 05 2018The Pauli--Villars regularization procedure confirms and sharpens the conclusions reached previously by covariant point splitting. The divergences in the stress tensor of a quantized scalar field interacting with a static scalar potential are isolated ... More
Wannier-function-based constrained DFT with nonorthogonality-correcting Pulay forces in application to the reorganization effects in graphene-adsorbed pentaceneFeb 05 2018Pulay terms arise in the Hellman-Feynman forces in electronic structure calculations when one employs a basis set made of localized orbitals that move with their host atoms. If the total energy of the system depends on a subspace population, defined in ... More
Diffraction of a CW atom laser in the Raman-Nath regimeFeb 05 2018Atom interferometry is the most successful technique for precision metrology. However, current interferometers using ultracold atoms allows one to probe the interference pattern only momentarily and has finite duty cycle, resulting in an aliasing effect ... More
PhD thesis: Homological Quantum Codes Beyond the Toric CodeFeb 05 2018PhD thesis investigating homological quantum codes derived from curved and higher dimensional geometries. In the first part we will consider closed surfaces with constant negative curvature. We show how such surfaces can be constructed and enumerate all ... More
Experimental realization of noise-induced adiabaticity in nuclear magnetic resonanceFeb 05 2018The adiabatic evolution is the dynamics of an instantaneous eigenstate of a slowly varing Hamiltonian. Recently, an interesting phenomenon shows up that white noises can enhance and even induce adiabaticity, which is in contrast to previous perception ... More
Grassmann representation in qubit informatics and superlogicFeb 05 2018The Grassmann representation for the system of qubits, is considered. The treatment is based on natural description of the qubits system as fermions and uses coherent states of fermions. The quantum logic gates are represented in two forms - by symbols ... More
All unital qubit channels are $4$-noisy operationsFeb 05 2018We show that any unital qubit channel can be implemented by letting the input system interact unitarily with a $4$-dimensional environment in the maximally mixed state and then tracing out the environment. We also provide an example where the dimension ... More
Voltage-Controlled Superconducting Quantum BusFeb 05 2018We demonstrate the ability of an epitaxial semiconductor-superconductor nanowire to serve as a field-effect switch to tune a superconducting cavity. Two superconducting gatemon qubits are coupled to the cavity, which acts as a quantum bus. Using a gate ... More
Hybrid systems for the dissipative preparation of mechanical Schrödinger catsFeb 05 2018We present a method to implement two-phonon interactions between mechanical resonators and spin qubits in hybrid setups, and show that these systems can be applied for the dissipative generation of nonclassical mechanical states. In particular, we demonstrate ... More
NV-Metamaterial: Tunable Quantum Hyperbolic Metamaterial Using Nitrogen-Vacancy Centers in DiamondFeb 05 2018Feb 06 2018We show that nitrogen-vacancy (NV) centers in diamond can produce a novel quantum hyperbolic metamaterial. We demonstrate that a hyperbolic dispersion relation in diamond with NV centers can be engineered and dynamically tuned by applying a magnetic field. ... More
Convex and Sequential Effect AlgebrasFeb 05 2018We present a mathematical framework for quantum mechanics in which the basic entities and operations have physical significance. In this framework the primitive concepts are states and effects and the resulting mathematical structure is a convex effect ... More
Integrable time-dependent Hamiltonians, solvable Landau-Zener models and Gaudin magnetsFeb 03 2018We solve the non-stationary Schrodinger equation for several time-dependent Hamiltonians, such as the BCS Hamiltonian with an interaction strength inversely proportional to time, periodically driven BCS and linearly driven inhomogeneous Dicke models as ... More
Arbitrarily accurate twin composite $π$ pulse sequencesFeb 03 2018We present three classes of symmetric broadband composite pulse sequences. The composite phases are given by analytic formulas (rational fractions of $\pi$) valid for any number of constituent pulses. The transition probability is expressed by simple ... More
Unlearning and Seyab's theorem: a dialogue about updating probabilityFeb 03 2018This dialogue explores the possibility of updating a probability as a consequence of unlearning, reversing the role of prior and posterior probabilities.
Quantum phase diagram of spin-$1$ $J_1-J_2$ Heisenberg model on the square lattice: an infinite projected entangled-pair state and density matrix renormalization group studyFeb 02 2018We study the spin-$1$ Heisenberg model on the square lattice with the antiferromagnetic nearest-neighbor $J_1$ and the next-nearest-neighbor $J_2$ couplings by using the infinite projected entangled-pair state (iPEPS) ansatz and density matrix renormalization ... More
Trapping CollapseFeb 02 2018Weak potential wells (or traps) in one and two dimensions, and the potential wells slightly deeper than the critical ones in three dimensions, feature shallow bound states with localization length much larger than the well radii. We address a simple fundamental ... More
Entropic bounds between two thermal equilibrium statesFeb 02 2018The positivity conditions of the relative entropy between two thermal equilibrium states $\hat{\rho}_1$ and $\hat{\rho}_2$ are used to obtain upper and lower bounds for the subtraction of their entropies, the Helmholtz potential and the Gibbs potential ... More
Coulomb-free and Coulomb-distorted recolliding quantum orbits in photoelectron holographyFeb 02 2018We perform a detailed analysis of the different types of orbits in the Coulomb Quantum Orbit Strong-field Approximation (CQSFA), ranging from direct to those undergoing hard collisions. We show that some of them exhibit clear counterparts in the standard ... More
From Quantum Foundations to Applications and BackFeb 02 2018Quantum non-locality has been an extremely fruitful subject of research, leading the scientific revolution towards quantum information science, in particular to device-independent quantum information processing. We argue that time is ripe to work on another ... More
Multipartite monogamous relations for Entanglement and DiscordFeb 01 2018The distribution of quantum correlations in multipartite systems play a significant role in several aspects of the quantum information theory. While it is well known that these quantum correlations can not be freely distributed, the way that it is shared ... More
$^{31}$P NMR study of discrete time-crystalline signatures in an ordered crystal of ammonium dihydrogen phosphateFeb 01 2018The rich dynamics and phase structure of driven systems includes the recently-described phenomenon of the "discrete time crystal" (DTC), a robust phase which spontaneously breaks the discrete time translation symmetry of its driving Hamiltonian. Experiments ... More
Quantum-Enhanced Plasmonic SensingFeb 01 2018Quantum resources can enhance the sensitivity of a device beyond the classical shot noise limit and, as a result, revolutionize the field of metrology through the development of quantum-enhanced sensors. In particular, plasmonic sensors, which are widely ... More
Generation of single and two-mode multiphoton states in waveguide QEDFeb 01 2018Single and two-mode multiphoton states are the cornerstone of many quantum technologies, e.g., metrology. In the optical regime these states are generally obtained combining heralded single-photons with linear optics tools and post-selection, leading ... More
Relations between the single-pass and double-pass transition probabilities in quantum systems with two and three statesFeb 01 2018In the experimental determination of the population transfer efficiency between discrete states of a coherently driven quantum system it is often inconvenient to measure the population of the target state. Instead, after the interaction that transfers ... More
Entanglement Swapping for Generation of Heralded Time-Frequency-Entangled Photon PairsFeb 01 2018Feb 06 2018Photonic time-frequency entanglement is a promising resource for quantum information processing technologies. We investigate swapping of continuous-variable entanglement in the time-frequency degree of freedom using three-wave mixing in the low-gain regime ... More
Current fluctuations in boundary-driven quantum spin chainsJan 31 2018Boundary-driven spin chains are paradigmatic non-equilibrium systems in both classical and quantum settings. In general it may not be possible to distinguish classical from quantum transport through monitoring the mean current, as both ballistic as well ... More
SO(3) "Nuclear Physics" with ultracold GasesJan 31 2018An ab initio calculation of nuclear physics from Quantum Chromodynamics (QCD), the fundamental SU(3) gauge theory of the strong interaction, remains an outstanding challenge. Here, we discuss the emergence of key elements of nuclear physics using an SO(3) ... More
Lindbladians with multiple steady states: theory and applicationsJan 31 2018Markovian master equations, often called Liouvillians or Lindbladians, are used to describe decay and decoherence of a quantum system induced by that system's environment. While a natural environment is detrimental to fragile quantum properties, an engineered ... More
Contextuality Analysis of the Double Slit Experiment (With a Glimpse Into Three Slits)Jan 31 2018The Contextuality-by-Default theory is illustrated on contextuality analysis of the idealized double-slit experiment. The system of contextually labeled random variables describing this experiment forms a cyclic system of rank 4, formally the same as ... More
Atomic-state diagnostics and optimization in cold-atom experimentsJan 31 2018Feb 02 2018We report on the creation, observation and optimization of superposition states of cold atoms. In our experiments, rubidium atoms are prepared in a magneto-optical trap and later, after switching off the trapping fields, Faraday rotation of a weak probe ... More
Quantum process tomography of linear and quadratically nonlinear optical systemsJan 31 2018A central task in quantum information processing is to characterize quantum processes. In the realm of optical quantum information processing, this amounts to characterizing the transformations of the mode creation and annihilation operators. This transformation ... More
Broadband thermal light with Bose-Einstein photon statistics from warm atomic vaporJan 31 2018We present the experimental observation of light with ideal thermal statistics generated in a warm atomic vapor. Statistical properties of the generated light field are tested both by the direct measurement of second-order correlation function and by ... More
Coherence area measurements of bright entangled twin beamsJan 31 2018Quantum states of light with multiple spatial modes are fundamental for quantum imaging and parallel quantum information processing. Thus, their characterization, which can be achieved through measurements of the coherence area, is an important area of ... More
Reconfigurable generation and measurement of mutually unbiased bases for time-bin quditsJan 31 2018We propose a new method for implementing mutually unbiased generation and measurement of time-bin qudits using a cascade of electro-optic phase modulator -- coded fiber Bragg grating pairs. Our approach requires only a single spatial mode and can switch ... More
Two-dimensional vortex quantum dropletsJan 31 2018It was recently found that the Lee-Huang-Yang (LHY) correction to the mean-field Hamiltonian suppresses the collapse and creates stable localized modes (two-component "quantum droplets", QDs) in two and three dimensions. We construct two-dimensional\ ... More
Zero field optical magnetic resonance study of phosphorus donors in 28-siliconJan 31 2018Donor spins in silicon are some of the most promising qubits for upcoming solid-state quantum technologies. The nuclear spins of phosphorus donors in enriched silicon have among the longest coherence times of any solid-state system as well as simultaneous ... More
Harmonic oscillators from displacement operators and thermodynamicsJan 30 2018In this investigation, the displacement operator is revisited. We established a connection of the Hermitian version of this operator with the well-known Weyl ordering. Besides, we characterized the quantum properties of a simple displaced harmonic oscillator, ... More
Noise-robust quantum sensing via optimal multi-probe spectroscopyJan 30 2018The dynamics of quantum systems are unavoidably influenced by their environment and in turn observing a quantum system (probe) can allow one to measure its environment: Measurements and controlled manipulation of the probe such as dynamical decoupling ... More
Interacting Qubit-Photon Bound States with Superconducting CircuitsJan 30 2018Qubits strongly coupled to a photonic crystal give rise to many exotic physical scenarios, beginning with single and multi-excitation qubit-photon dressed bound states comprising induced spatially localized photonic modes, centered around the qubits, ... More
Diagrammatic Reasoning beyond Clifford+T Quantum MechanicsJan 30 2018The ZX-Calculus is a graphical language for quantum mechanics. An axiomatisation has recently been proven to be complete for an approximatively universal fragment of quantum mechanics, the so-called Clifford+T fragment. We focus here on the expressive ... More
Extended Carnot bound for autonomous quantum refrigerators powered by non-thermal statesJan 30 2018In contrast to semi-classical refrigerators powered by ideal external work, quantum autonomous refrigerators do not benefit from external work or control and find their source of energy in ancillary systems. Frequently, the ancillary system considered ... More
On-chip excitation of single germanium-vacancies in nanodiamonds embedded in plasmonic waveguidesJan 30 2018Monolithic integration of quantum emitters in nanoscale plasmonic circuitry requires low-loss plasmonic configurations capable of confining light well below the diffraction limit. We demonstrate on-chip remote excitation of nanodiamond-embedded single ... More
Observation of interaction-induced gauge fields in a Bose-Einstein condensate based on micromotion control in a shaken two-dimensional latticeJan 30 2018We demonstrate an interaction-induced gauge field for Bose-Einstein condensates in a modulated two-dimensional optical lattice. The gauge field results from the synchronous coupling between the interactions and micromotion of the atoms. As a first step, ... More
Stochastic Representation of a Class of Non-Markovian Completely Positive EvolutionsJan 30 2018By modeling the interaction of an open quantum system with its environment through a natural generalization of the classical concept of continuous time random walk, we derive and characterize a class of non-Markovian master equations whose solution is ... More
Non-Reciprocal Transmission and Reflection of a Chirally-Coupled Quantum DotJan 30 2018We report non-reciprocal transmission and reflection for quantum dot exciton spins coupled to nanophotonic waveguides. A clear dependence on propagation direction is found for a chirally-coupled quantum dot, with spin up and spin down exciton spins coupling ... More
Strain engineering of the silicon-vacancy center in diamondJan 30 2018Jan 31 2018We control the electronic structure of the silicon-vacancy (SiV) color-center in diamond by changing its static strain environment with a nano-electro-mechanical system. This allows deterministic and local tuning of SiV optical and spin transition frequencies ... More