Monte Carlo simulations of the electron short-range quantum ordering in Coulomb systems: Reducing the "fermionic sign problem"

Vladimir Filinov; Pavel Levashov; Alexander Larkin

doi:10.1088/1751-8121/ac40e3

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arXiv · 2105.04198

Monte Carlo simulations of the electron short-range quantum ordering in Coulomb systems: Reducing the "fermionic sign problem"

Vladimir Filinov·Pavel Levashov·Alexander Larkin

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Abstract

To account for the interference effects of the Coulomb and exchange interactions of electrons a new path integral representation of the density matrix has been developed in the canonical ensemble at finite temperatures. The developed representation allows to reduce the notorious ``fermionic sign problem'' in the Monte Carlo simulations of fermionic systems. The obtained results for pair distribution functions in plasma and uniform electron gas demonstrate the short-range quantum ordering of electrons associated with exchange excitons in the literature. This fine physical effect was not observed earlier in standard path integral Monte Carlo simulations.

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Vladimir Filinov, Pavel Levashov, Alexander Larkin. 2021-05-10. Monte Carlo simulations of the electron short-range quantum ordering in Coulomb systems: Reducing the "fermionic sign problem". https://doi.org/10.1088/1751-8121%2Fac40e3

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