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Variation Principle for Calculation of Many-Particle Effects in Crystals

Halina V. Grushevskaya·Leonid I. Gurskii
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Abstract

Variation principle has been developed to calculate many-particle effects in crystals. Within the framework of quasi-particle concept the variation principle has been used to find one-electron states with taking into account of effects due to non-locality of electronic density functional in electromagnetic fields. A secondary quantized density matrix was used to find the Green function of a quasiparticle and changes of its effective mass due to correlated motion of interacting electrons.

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Halina V. Grushevskaya, Leonid I. Gurskii. 2006-01-28. Variation Principle for Calculation of Many-Particle Effects in Crystals. https://arxiv.org/abs/quant-ph/0601192

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