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In the study of d-dimensional quantum channels $(d \geq 2)$, an assumption which is not very restrictive, and which has a natural physical interpretation, is that the corresponding Kraus operators form a representation of a Lie algebra.…

Quantum Physics · Physics 2007-05-23 William Gordon Ritter

We provide a simple analytic relation which connects the density operator of the radiation field with the number probabilities. The problem of experimentally "sampling" a general matrix elements is studied, and the deleterious effects of…

Quantum Physics · Physics 2010-12-17 Stefano Mancini , Paolo Tombesi , Vladimir I. Manko

Bohr's complementarity principle is of fundamental historic and conceptual importance for Quantum Mechanics (QM), and states that, with a given experimental apparatus configuration, one can observe either the wave-like or the particle-like…

Quantum Physics · Physics 2021-02-18 Mauro B. Pozzobom , Marcos L. W. Basso , Jonas Maziero

The $N$-representability problem for non-collinear spin-polarized densities was left open in the pioneering work of von Barth and Hedin setting up the Kohn-Sham density functional theory for magnetic compounds. In this letter, we…

Mathematical Physics · Physics 2025-05-20 David Gontier

We derive a new kind of effective broadband polarization device using the analogy between the equation for the polarization of light, propagating through an optically anisotropic medium, and the optical Bloch equation in adiabatic regime,…

Optics · Physics 2011-11-29 A. A. Rangelov

We develop convergent variational perturbation theory for quantum statistical density matrices. The theory is applicable to polynomial as well as nonpolynomial interactions. Illustrating the power of the theory, we calculate the…

Quantum Physics · Physics 2009-10-31 M. Bachmann , H. Kleinert , A. Pelster

We present systematic construction of probability and probability current densities operators for one-band single particle Pauli equations starting from the operators in Dirac electron model within Second Quantized Approach. These operators…

Mesoscale and Nanoscale Physics · Physics 2017-08-15 E. L. Rumyantsev , P. E. Kunavin

We give an improved criterion of genuine multipartite entanglement for an important class of multipartite quantum states using generalized Bloch representations of the density matrices. The practical criterion is designed based on the Weyl…

Quantum Physics · Physics 2023-09-08 Xia Zhang , Naihuan Jing , Hui Zhao , Ming Liu , Haitao Ma

In this study, we explore a form of quantum circuit complexity that extends to open systems. To illustrate our methodology, we focus on a basic model where the projective Hilbert space of states is depicted by the set of orientations in the…

Quantum Physics · Physics 2024-10-07 E. M. F. Curado , S. Faci , J. P. Gazeau , T. Koide , A. C. Maioli , D. Noguera

In this survey the possible approaches to the description of the evolution of states of quantum many-particle systems by means of the possible modifications of the density operator which kernel known as density matrix are considered. In…

Mathematical Physics · Physics 2020-01-14 V. I. Gerasimenko

A representation is put forward for wave functions of quantum particles in periodic lattice potentials subjected to homogeneous time-periodic forcing, based on an expansion with respect to Bloch-like states which embody both the spatial and…

Quantum Gases · Physics 2011-08-10 Stephan Arlinghaus , Martin Holthaus

In the present article, we consistently develop the main issues of the Bloch vectors formalism for an arbitrary finite-dimensional quantum system. In the frame of this formalism, qudit states and their evolution in time, qudit observables…

Quantum Physics · Physics 2024-01-30 Elena R. Loubenets , Maxim S. Kulakov

We study genuine tripartite entanglement and multipartite entanglement in arbitrary $n$-partite quantum systems based on complete orthogonal basis (COB). While the usual Bloch representation of a density matrix uses three types of…

Quantum Physics · Physics 2024-02-21 Hui Zhao , Jia Hao , Jing Li , Shao-Ming Fei , Naihuan Jing , Zhi-Xi Wang

Generalized quantum measurements with N distinct outcomes are used for determining the density matrix, of order d, of an ensemble of quantum systems. The resulting probabilities are represented by a point in an N-dimensional space. It is…

Quantum Physics · Physics 2009-10-31 Asher Peres , Daniel Terno

The density matrix of a non-relativistic quantum system, divided into $N$ sub-systems, is rewritten in terms of the set of all partitioned density matrices for the system. For the case where the different sub-systems are distinguishable, we…

Quantum Physics · Physics 2018-12-19 Timothy Cox , Philip C. E. Stamp

New inequalities for tomographic probability distributions and density matrices of qutrit states are obtained by means of generalization of qubit portrait method. The approach based on the qudit portrait method to get new entropic…

Quantum Physics · Physics 2019-02-12 V. N. Chernega , O. V. Man'ko , V. I. Man'ko

The random matrix ensembles are applied to the quantum statistical two-dimensional systems of electrons. The quantum systems are studied using the finite dimensional real, complex and quaternion Hilbert spaces of the eigenfunctions. The…

Statistical Mechanics · Physics 2015-06-24 Maciej M. Duras

A visualization scheme for dynamics of a qudit polarization vector in a time-dependent magnetic field is presented by solving equations for a density matrix in Hermitian basis. This is realized by means of mapping solution for the…

Quantum Physics · Physics 2016-08-16 E. A. Ivanchenko

We derive transformation formulas for the generalized polarization tensors under rigid motions and scaling in three dimensions, and use them to construct an infinite number of invariants under those transformations. These invariants can be…

Analysis of PDEs · Mathematics 2012-12-17 Habib Ammari , Daewon Chung , Hyeonbae Kang , Han Wang

We introduce Quantum Time-Frequency Analysis, which expands the approach of Quantum Harmonic Analysis to include modulations of operators in addition to translations. This is done by a projective representation of double-phase space, and we…

Functional Analysis · Mathematics 2024-03-04 Franz Luef , Henry McNulty
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