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arXiv · 2104.03530

Ground state of one-dimensional fermion-phonon systems

Tadahiro Miyao·Seigo Okida·Hayato Tominaga
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Abstract

A new framework for the reflection positivity, based on order-preserving operator inequalities, is proposed. This framework is utilized to investigate one-dimensional fermion-phonon systems, with a particular focus on the detailed examination of ground state properties. Our analysis reveals that the reflection positivity provides a consistent description of the charge-density-wave (CDW) order in such systems. Additionally, we establish the existence of CDW long-range order in the ground state when the Coulomb interaction is long range.

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Tadahiro Miyao, Seigo Okida, Hayato Tominaga. 2021-04-08. Ground state of one-dimensional fermion-phonon systems. https://arxiv.org/abs/2104.03530

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