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Related papers: A new Phase Space Density for Quantum Expectations

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We study the efficiency of quantum algorithms which aim at obtaining phase space distribution functions of quantum systems. Wigner and Husimi functions are considered. Different quantum algorithms are envisioned to build these functions,…

Quantum Physics · Physics 2007-05-23 M. Terraneo , B. Georgeot , D. L. Shepelyansky

To reconstruct a mixed or pure quantum state of a spin s is possible through coherent states: its density matrix is fixed by the probabilities to measure the value s along 4s(s+1) appropriately chosen directions in space. Thus, after…

Quantum Physics · Physics 2007-05-23 Stefan Weigert

Motivated by some well-known results in the phase space description of quantum optics and quantum information theory, we aim to describe the formalism of quantum field theory by explicitly considering the holomorphic representation for a…

Quantum Physics · Physics 2020-10-28 Jasel Berra-Montiel , Alberto Molgado

We construct a semiclassical phase-space density of Schur vectors in non-Hermitian quantum systems. Each Schur vector is associated to a single Planck cell. The Schur states are organised according to a classical norm landscape on phase…

Quantum Physics · Physics 2023-07-28 Joseph Hall , Simon Malzard , Eva-Maria Graefe

The Wigner function of quantum systems is an effective instrument to construct the approximate classical description of the systems for which the classical approximation is possible. During the last time, the Wigner function formalism is…

Quantum Physics · Physics 2009-11-10 Constantin V. Usenko

Bochner's theorem gives the necessary and sufficient conditions on a function such that its Fourier transform corresponds to a true probability density function. In the Wigner phase space picture, quantum Bochner's theorem gives the…

Quantum Physics · Physics 2015-03-11 Ninnat Dangniam , Christopher Ferrie

In spite of its fundamental importance in quantum science and technology, the experimental certification of nonclassicality is still a challenging task, especially in realistic scenarios where losses and noise imbue the system. Here, we…

Quantum Physics · Physics 2021-01-29 Nicola Biagi , Martin Bohmann , Elizabeth Agudelo , Marco Bellini , Alessandro Zavatta

The Husimi phase distribution, an experimentally measurable quantity, is investigated for single-mode and two-mode squeezed vacuum states. The analysis highlights that non-Gaussian operations, i.e., photon subtraction (PS), photon addition…

Quantum Physics · Physics 2025-07-23 Ramniwas Meena , Chandan Kumar , Subhashish Banerjee

We show that the dynamics of a closed quantum system obeys the Hamilton variation principle. Even though quantum particles lack well-defined trajectories, their evolution in the Husimi representation can be treated as a flow of…

Quantum Physics · Physics 2022-03-02 Dmitry V. Zhdanov , Denys I. Bondar

We obtain a positive probability distribution or Q-function for an arbitrary fermionic many-body system. This is different to previous Q-function proposals, which were either restricted to a subspace of the overall Hilbert space, or used…

Quantum Physics · Physics 2015-03-27 Laura E. C. Rosales-Zarate , P. D. Drummond

We propose and simulate a protocol to evolve a quantum particle forward in time such that its trajectory closely matches that of the particle's Newtonian counterpart. Using short bursts of Schr\"odinger time-evolution interleaved with…

Quantum Physics · Physics 2025-10-21 Youheng Zheng

Phase-space representations based on coherent states (P, Q, Wigner) have been successful in the creation of stochastic differential equations (SDEs) for the efficient stochastic simulation of high dimensional quantum systems. However many…

Quantum Physics · Physics 2015-05-14 M. R. Hush , A. R. R. Carvalho , J. J. Hope

Husimi distributions and Wigner distributions are well-known quasi-probability distributions which appear in several contexts. In this paper, we show some remarkable aspects of these distribution functions related to geometric structures of…

Quantum Physics · Physics 2011-01-28 Ryo Harada

This paper presents a hybrid classical-quantum program for density estimation and supervised classification. The program is implemented as a quantum circuit in a high-dimensional quantum computer simulator. We show that the proposed quantum…

Using Husimi function approach, we study the ``quantum phase space'' of a harmonic oscillator interacting with a plane monochromatic wave. We show that in the regime of weak chaos, the quantum system has the same symmetry as the classical…

Quantum Physics · Physics 2009-10-31 G. P. Berman , V. Ya. Demikhovskii , D. I. Kamenev

In this paper we will turn our attention to the problem of obtaining phase-space probability density functions. We will show that it is possible to obtain functions which assume only positive values over all its domain of definition.

Quantum Physics · Physics 2007-05-23 L. S. F. Olavo

A new microcanonical equilibrium state is introduced for quantum systems with finite-dimensional state spaces. Equilibrium is characterised by a uniform distribution on a level surface of the expectation value of the Hamiltonian. The…

Quantum Physics · Physics 2007-10-25 Dorje C. Brody , Daniel W. Hook , Lane P. Hughston

This article outlines a novel interpretation of quantum theory: the Q-based interpretation. The core idea underlying this interpretation, recently suggested for quantum field theories by Drummond and Reid [2020], is to interpret the phase…

Quantum Physics · Physics 2024-09-23 Simon Friederich

We devise a method to certify nonclassical features via correlations of phase-space distributions by unifying the notions of quasiprobabilities and matrices of correlation functions. Our approach complements and extends recent results that…

Quantum Physics · Physics 2020-10-21 Martin Bohmann , Elizabeth Agudelo , Jan Sperling

We represent both the states and the evolution of a quantum computer in phase space using the discrete Wigner function. We study properties of the phase space representation of quantum algorithms: apart from analyzing important examples,…

Quantum Physics · Physics 2009-11-07 Cesar Miquel , Juan Pablo Paz , Marcos Saraceno