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arXiv · 1703.04448

Peculiarities of momentum distribution functions of strongly correlated charged fermions

Abstract

The new numerical version of the Wigner approach to quantum mechanics for treatment thermodynamic properties of strongly coupled systems of particles has been developed for extreme conditions, when analytical approximations obtained in different kind of perturbation theories can not be applied. Explicit analytical expression of the Wigner function has been obtained in linear and harmonic approximations. Fermi statistical effects are accounted by effective pair pseudopotential depending on coordinates, momenta and degeneracy parameter of particles and taking into account Pauli blocking of fermions. The new quantum Monte-Carlo method for calculations of average values of arbitrary quantum operators has been proposed. Calculations of the momentum distribution function of the degenerate ideal Fermi gas have been carried out for testing the developed approach. Comparison of obtained momentum distribution function of strongly correlated Coulomb systems of particles with Maxwell -- Boltzmann and Fermi distributions shows the significant influence of interparticle interaction both at small momenta and in the high energy quantum 'tails'.

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BibTeXRIS

A. S. Larkin, V. S. Filinov, V. E. Fortov. 2017-05-04. Peculiarities of momentum distribution functions of strongly correlated charged fermions. https://doi.org/10.1088/1751-8121%2Faa98d0

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