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Related papers: Universal density matrix for the phase space

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The Weyl-Wigner representation of quantum mechanics allows one to map the density operator in a function in phase space - the Wigner function - which acts like a probability distribution. In the context of statistical mechanics, this…

Quantum Physics · Physics 2023-08-31 Marcos Gil de Oliveira , Alfredo Miguel Ozorio de Almeida

In this paper we generalize the concept of Wigner function in the case of quantum mechanics with a minimum length scale arising due to the application of a generalized uncertainty principle (GUP). We present the phase space formulation of…

High Energy Physics - Theory · Physics 2021-01-28 Prathamesh Yeole , Vipul Kumar , Kaushik Bhattacharya

The quasiprobability distribution of the discrete Wigner function provides a complete description of a quantum state and is, therefore, a useful alternative to the usual density matrix description. Moreover, the experimental quantum state…

Quantum Physics · Physics 2023-10-13 Deepesh Khushwani , Priya Batra , V. R. Krithika , T. S. Mahesh

Decoherence phenomena are pervasive in the arena of nanostructures but perhaps even more so in the study of the fundamentals of quantum mechanics and quantum computation. Since there has been little overlap between the studies in both…

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

In this work we study the Wigner functions, which are the quantum analogues of the classical phase space density, and show how a full rigorous semiclassical scheme for all orders of \hbar can be constructed for them without referring to the…

Chaotic Dynamics · Physics 2009-11-07 Gregor Veble , Marko Robnik , Valery Romanovski

The quantum state of a light beam can be represented as an infinite dimensional density matrix or equivalently as a density on the plane called the Wigner function. We describe quantum tomography as an inverse statistical problem in which…

Statistics Theory · Mathematics 2007-06-13 L. M. Artiles , R. D. Gill , M. I. Guta

The Lindblad equation governs general markovian evolution of the density operator in an open quantum system. An expression for the rate of change of the Wigner function as a sum of integrals is one of the forms of the Weyl representation…

Quantum Physics · Physics 2009-11-07 Alfredo M. Ozorio de Almeida

The spatial Fourier spectrum of the electron density distribution in a finite 1D system and the distribution function of electrons over single-particle states are studied in detail to show that there are two universal features in their…

Strongly Correlated Electrons · Physics 2019-08-09 Yasha Gindikin , Vladimir A. Sablikov

The formalism of classical and quantum mechanics on phase space leads to symplectic and Heisenberg group representations, respectively. The Wigner functions give a representation of the quantum system using classical variables. The…

Quantum Physics · Physics 2007-05-23 Ajay Patwardhan

The damping of the harmonic oscillator is studied in the framework of the Lindblad theory for open quantum systems. A generalization of the fundamental constraints on quantum mechanical diffusion coefficients which appear in the master…

Quantum Physics · Physics 2015-06-26 A. Isar , A. Sandulescu , H. Scutaru , E. Stefanescu , W. Scheid

A phase space formulation of the filtering process upon an incident quantum state is developed. This formulation can explain the results of both quantum interference and delayed-choice experiments without making use of the controversial…

Quantum Physics · Physics 2009-11-10 Daniela Dragoman

In the physics literature the spectral form factor (SFF), the squared Fourier transform of the empirical eigenvalue density, is the most common tool to test universality for disordered quantum systems, yet previous mathematical results have…

Mathematical Physics · Physics 2023-07-26 Giorgio Cipolloni , László Erdős , Dominik Schröder

The phase space representation for a q-deformed model of the quantum harmonic oscillator is constructed. We have found explicit expressions for both the Wigner and Husimi distribution functions for the stationary states of the…

Mathematical Physics · Physics 2007-05-23 E. I. Jafarov , S. Lievens , S. M. Nagiyev , J. Van der Jeugt

For a quantum system, a density matrix rho that is not pure can arise, via averaging, from a distribution mu of its wave function, a normalized vector belonging to its Hilbert space H. While rho itself does not determine a unique mu,…

Quantum Physics · Physics 2007-05-23 Sheldon Goldstein , Joel L. Lebowitz , Roderich Tumulka , Nino Zanghi

Quantum Information is a new area of research which has been growing rapidly since the last decade. This topic is very close to potential applications to the so called Quantum Computer. In our point of view it makes sense to develop a more…

Dynamical Systems · Mathematics 2011-04-18 A. Baraviera , C. F. Lardizabal , A. O. Lopes , M. Terra Cunha

The quantum state of a system of qubits can be represented by a Wigner function on a discrete phase space, each axis of the phase space taking values in a finite field. Within this framework, we show that one can make sense of the notion of…

Quantum Physics · Physics 2007-05-23 William K. Wootters , Daniel M. Sussman

We present a phase space description of the process of quantum teleportation for a system with an $N$ dimensional space of states. For this purpose we define a discrete Wigner function which is a minor variation of previously existing ones.…

Quantum Physics · Physics 2009-11-07 Juan Pablo Paz

The original Wigner function provides a way of representing in phase space the quantum states of systems with continuous degrees of freedom. Wigner functions have also been developed for discrete quantum systems, one popular version being…

Quantum Physics · Physics 2009-11-10 Kathleen S. Gibbons , Matthew J. Hoffman , William K. Wootters

This paper presents a comprehensive investigation of the problem of a harmonic oscillator with time-depending frequencies in the framework of the Vlasov theory and the Wigner function apparatus for quantum systems in the phase space. A new…

Quantum Physics · Physics 2023-05-16 E. E. Perepelkin , B. I. Sadovnikov , N. G. Inozemtseva , A. A. Korepanova

In the context of phase-space quantization, matrix elements and observables result from integration of c-number functions over phase space, with Wigner functions serving as the quasi-probability measure. The complete sets of Wigner…

High Energy Physics - Theory · Physics 2009-10-02 Thomas Curtright , Tsuneo Uematsu , Cosmas Zachos