Paraelectric-to-ferroelectric crossover and electron dynamics from time-dependent Hartree-Fock calculations

Toshifumi Itakura

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arXiv · 0711.1021

Paraelectric-to-ferroelectric crossover and electron dynamics from time-dependent Hartree-Fock calculations

Toshifumi Itakura

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Abstract

In recent years, researchers have discovered various excited states of electrons having an excited domain with a structural order different from the original one. We examine a dynamics of electron system and phonon system by using the time-dependent Hartree-Fock approximation. We examine time evolution with spin degree of freedom. We found a thermally excited paraelectric-to-ferroelectric crossover. The metastable state is spin pierls state. We also examine the Landau expansion of electron system at quarter-filled.

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Toshifumi Itakura. 2007-11-07. Paraelectric-to-ferroelectric crossover and electron dynamics from time-dependent Hartree-Fock calculations. https://arxiv.org/abs/0711.1021

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