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Related papers: Wigner Function of Observed Quantum Systems

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In this paper, the ground state Wigner function of a many-body system is explored theoretically and numerically. First, an eigenvalue problem for Wigner function is derived based on the energy operator of the system. The validity of finding…

Quantum Physics · Physics 2021-11-24 Hongfei Zhan , Zhenning Cai , Guanghui Hu

Interactions between charged particles and light occur in real space and time, yet quantum field theory usually describes them in momentum space. Whereas this approach is well suited for calculating emission probabilities and cross…

In the beginning of the 1950's, Wigner introduced a fundamental deformation from the canonical quantum mechanical harmonic oscillator, which is nowadays sometimes called a Wigner quantum oscillator or a parabose oscillator. Also, in quantum…

Mathematical Physics · Physics 2008-06-27 E. I. Jafarov , S. Lievens , J. Van der Jeugt

We study a generalization of the Wigner function to arbitrary tuples of hermitian operators. We show that for any collection of hermitian operators A1...An , and any quantum state there is a unique joint distribution on R^n, with the…

Quantum Physics · Physics 2020-07-09 René Schwonnek , Reinhard F. Werner

We study the process of vacuum decay in quantum field theory focusing on the stochastic aspects of the interaction between long and short-wavelength modes. This interaction results in a diffusive behavior of the reduced Wigner function…

High Energy Physics - Phenomenology · Physics 2009-11-07 Esteban Calzetta , Albert Roura , Enric Verdaguer

The two-dimensional Radon transform of the Wigner quasiprobability is introduced in canonical form and the functions playing a role in its inversion are discussed. The transformation properties of this Radon transform with respect to…

Quantum Physics · Physics 2016-06-29 Alfred Wünsche

In this work we present the formal background used to develop the methods used in earlier works to extend the truncated Wigner representation of quantum and atom optics in order to address multi-time problems. The truncated Wigner…

Quantum Physics · Physics 2015-06-16 L I Plimak , M K Olsen

Highly nonclassical character of optical quantum detectors, such as single-photon detectors, is essential for preparation of quantum states of light and a vast majority of applications in quantum metrology and quantum information…

Quantum Physics · Physics 2021-02-24 Josef Hloušek , Miroslav Ježek , Jaromír Fiurášek

The coherence properties of the classical waves are discussed in terms of the Cauchy problem for the wave equation, and of a discrete representation by an ensemble of Hamiltonian systems. Wave quanta are related to specific "action fields",…

Quantum Physics · Physics 2021-09-15 M. Grigorescu

We develop a general formalism, based on the Wigner function representation of continuous-variable quantum states, to describe the action of an arbitrary conditional operation on a multimode Gaussian state. We apply this formalism to…

Quantum Physics · Physics 2020-10-28 Mattia Walschaers , Valentina Parigi , Nicolas Treps

Density matrices and Discrete Wigner Functions are equally valid representations of multiqubit quantum states. For density matrices, the partial trace operation is used to obtain the quantum state of subsystems, but an analogous…

Quantum Physics · Physics 2017-12-08 K. Srinivasan , G. Raghavan

We derive an analytical expression of a Wigner function that approximately describes the time evolution of the one-dimensional motion of a particle in a nonharmonic potential. Our method involves two exact frame transformations, accounting…

Utilizing the tools of quantum optics to prepare and manipulate quantum states of motion of a mechanical resonator is currently one of the most promising routes to explore non-classicality at a macroscopic scale. An important quantum…

Quantum Physics · Physics 2015-02-05 M. R. Vanner , I. Pikovski , M. S. Kim

We first review the usefulness of the Wigner distribution functions (WDF), associated with Lindblad and pre-master equations, for analyzing a host of problems in Quantum Optics where dissipation plays a major role, an arena where weak…

Quantum Physics · Physics 2009-11-10 R. F. O'Connell

The use of quantum information in technology promises to supersede the so-called classical devices used nowadays. Understanding what features are inherently non-classical is crucial for reaching better-than-classical performance. This…

Quantum Physics · Physics 2022-04-20 Pierre-Emmanuel Emeriau

Relativistic quantum effects on physical observables of scalar charged particles are studied. Possible peculiarities of their behavior that can be verified in an experiment can confirm several fundamental conceptions of quantum mechanics.…

Quantum Physics · Physics 2007-05-23 B. I. Lev , A. A. Semenov , C. V. Usenko

The Wigner-function formalism is a well known approach to model charge transport in semiconductor nanodevices. Primary goal of the present article is to point out and explain intrinsic limitations of the conventional quantum-device modeling…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Roberto Rosati , Fabrizio Dolcini , Rita Claudia Iotti , Fausto Rossi

The mathematical description of the quantum harmonic oscillator is essentially based on the Gaussian function. In the case of a quantum oscillator with finite-dimensional Hilbert space, the position space consists in a finite number of…

Mathematical Physics · Physics 2015-12-09 Nicolae Cotfas

A recently introduced hierarchy of states of a single mode quantised radiation field is examined for the case of centered Guassian Wigner distributions. It is found that the onset of squeezing among such states signals the transition to the…

Quantum Physics · Physics 2008-12-18 Arvind , N. Mukunda , R. Simon

In these two related parts we present a set of methods, analytical and numerical, which can illuminate the behaviour of quantum system, especially in the complex systems. The key points demonstrating advantages of this approach are: (i)…

Quantum Physics · Physics 2009-11-11 Antonina N. Fedorova , Michael G. Zeitlin