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Related papers: Operational quasiprobabilities for qudits

200 papers

We extend Einstein's hole argument into the quantum domain, and argue that quantum observables for quasiclassical superpositional states of gravitational fields require additional information to be well-defined, namely, relative positions…

Quantum Physics · Physics 2009-02-13 I. Schmelzer

How to give a statistical description of thermodynamics in quantum systems is an open fundamental question. Concerning the work, the presence of initial quantum coherence in the energy basis can give rise to a quasiprobability of work,…

Quantum Physics · Physics 2022-11-15 Gianluca Francica

A unification of the set of quasiprobability representations using the mathematical theory of frames was recently developed for quantum systems with finite-dimensional Hilbert spaces, in which it was proven that such representations require…

Quantum Physics · Physics 2010-10-18 Christopher Ferrie , Ryan Morris , Joseph Emerson

The Kirkwood-Dirac quasiprobability distribution, intimately connected with the quantum correlation function of two observables measured at distinct times, is becoming increasingly relevant for fundamental physics and quantum technologies.…

We introduce an experimental test for ruling out classical explanations for the statistics obtained when measuring arbitrary observables at arbitrary times using individual detectors. This test requires some trust in the measurements,…

Quantum Physics · Physics 2019-03-27 Patrick P. Potts

This article comprises a review of both the quasi-probability representations of infinite-dimensional quantum theory (including the Wigner function) and the more recently defined quasi-probability representations of finite-dimensional…

Quantum Physics · Physics 2011-10-18 Christopher Ferrie

We report on the first experimental reconstruction of an entanglement quasiprobability. In contrast to related techniques, the negativities in our distributions are a necessary and sufficient identifier of separability and entanglement and…

Quantum Physics · Physics 2019-02-08 J. Sperling , E. Meyer-Scott , S. Barkhofen , B. Brecht , C. Silberhorn

We show an operational approach to bilocality with quasi-probability distributions and quasi-stochastic processes. This approach clearly demonstrates that negative probabilities are necessary to violate bilocality. It also highlights a…

Quantum Physics · Physics 2023-02-08 Kelvin Onggadinata , Pawel Kurzynski , Dagomir Kaszlikowski

In this tutorial, we present the definition, interpretation and properties of some of the main quasiprobabilities that can describe the statistics of measurement outcomes evaluated at two or more times. Such statistics incorporate the…

Quantum Physics · Physics 2024-09-23 Stefano Gherardini , Gabriele De Chiara

Recent work has revealed the central role played by the Kirkwood-Dirac quasiprobability (KDQ) as a tool to properly account for non-classical features in the context of condensed matter physics (scrambling, dynamical phase transitions)…

The impossibility of measuring noncommuting quantum mechanical observables is one of the most fascinating consequences of the quantum mechanical postulates. Hence, to date the investigation of quantum measurement and projection is a…

Mesoscale and Nanoscale Physics · Physics 2010-09-06 Adam Bednorz , Wolfgang Belzig

We provide several applications of a previously introduced isomorphism between physical operations acting on two systems and entangled states [1]. We show: (i) how to implement (weakly) non-local two qubit unitary operations with a small…

Quantum Physics · Physics 2009-11-06 W. Dür , J. I. Cirac

Quantum batteries can be charged by performing a work ``instantaneously'' in the limit of a large number of cells, achieving a so-called quantum advantage. In general, the work exhibits statistics that can be represented by a…

Quantum Physics · Physics 2026-05-29 Gianluca Francica

Complementarity and entanglement are fundamental features of Quantum Mechanics that were recently related in triality equalities that involve quantum coherence, the wave aspect of a qubit, and quantum predictability and quantum…

Quantum Physics · Physics 2022-09-09 Marcos L. W. Basso , Jonas Maziero

Quasianalytic contractions form the crucial class in the quest for proper invariant and hyperinvariant subspaces for asymptotically non-vanishing Hilbert space contractions. The property of quasianalycity relies on the concepts of unitary…

Functional Analysis · Mathematics 2015-03-24 László Kérchy

We introduce a method for testing quantum correlations in terms of quasiprobability functions in the presence of noise. We analyze the effects of measurement imperfection and thermal environment on quantum correlations and show that their…

Quantum Physics · Physics 2020-07-09 Seung-Woo Lee , Jaewan Kim , Wonmin Son

Quantum operations are used to describe the observed probability distributions and conditional states of the measured system. In this paper, we address the problem of their joint measurability (coexistence). We derive two equivalent…

Quantum Physics · Physics 2009-08-21 Teiko Heinosaari , Daniel Reitzner , Peter Stano , Mario Ziman

Determining the conditions under which positive operator-valued measures (POVMs), the most general class of quantum measurements, outperform projective measurements remains a challenging and largely unresolved problem. Of particular…

We theoretically describe the weak measurement of a two-level system (qubit) and quantify the degree to which such a qubit measurement has a quantum non-demolition (QND) character. The qubit is coupled to a harmonic oscillator which…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Luca Chirolli , Guido Burkard

Polarization quasi-probability distribution (PQPD) is defined in the Stokes space, and it enables the calculation of mean values and higher-order moments for polarization observables using simple algebraic averaging. It can be reconstructed…

Quantum Physics · Physics 2013-08-21 M. V. Chekhova , F. Ya. Khalili