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arXiv · 1407.7770

Many-particle quantum hydrodynamics: Basic principles and fundamental applications

P. A. Andreev·L. S. Kuz'menkov
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Abstract

We present a detailed derivation of the continuity, Euler, and energy balance equations from many particle Schrodinger equation. Interparticle interaction is explicitly considered as the Coulomb interaction. We show the QHD equations in a form suitable for low dimensional systems. The QHD equations in the cylindrical and spherical coordinates are presented as well. We present a method of non-linear Schrodinger equation derivation from the QHD equations. We describe a method of exchange interaction calculation for two- and three-dimensional quantum plasmas. We discuss explicit form and area of applicability of equations of state for 1D, 2D, and 3D degenerate electrons. We explicitly consider equations of state for degenerate electron gas in an external magnetic field. Considering QHD equations in cylindrical coordinates we focus our attention on the quantum part of the inertia forces and contribution of the quantum Bohm potential to the spectrum of quantum cylindrical waves. Collective excitations of 2DEG on spherical surface are considered. Equation of state for degenerate 2DEG on a spherical surface is obtained. We apply the QHD equations to small amplitude collective excitations in linear regime of QHD equations. We consider the Langmuir waves in 1D, 2D, and 3D quantum plasmas including the exchange Coulomb interaction. Considering quantum plasmas located in an external magnetic field we focus our attention on longitudinal waves propagating perpendicular to the external magnetic field. We present this consideration for 1D, 2D, and 3D plasmas. We discuss dependence of the exchange interaction on rate of polarization of spins in the external magnetic field. We include dependence of the pressure of degenerate electrons on the strength of the external magnetic field via the change of occupation of quantum states at application of an external magnetic field.

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P. A. Andreev, L. S. Kuz'menkov. 2014-07-29. Many-particle quantum hydrodynamics: Basic principles and fundamental applications. https://arxiv.org/abs/1407.7770

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