Phonon Bose-Einstein condensation in a Hubbard-phonon interacting system with infrared divergence

Yoshitsugu Sekine

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arXiv · 1308.5589

Phonon Bose-Einstein condensation in a Hubbard-phonon interacting system with infrared divergence

Yoshitsugu Sekine

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Abstract

We show that a finite Hubbard-phonon interacting system exhibits phonon BEC at sufficiently low temperature. We also have the gauge symmetry breaking for phonons. The key tools are a unitary transformation introduced by Arai and Hirokawa \protect{\cite{AH1}} and the Araki-Woods representation. This system is essentially the same as a free system or the van Hove model.

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Yoshitsugu Sekine. 2013-08-26. Phonon Bose-Einstein condensation in a Hubbard-phonon interacting system with infrared divergence. https://arxiv.org/abs/1308.5589

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