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arXiv · 1101.0247

Fluctuation induced non-canonical BCS states: a mechanism for pseudogap

Lei Gu
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Abstract

We pose the question of what effect the statistical fluctuation causes if it induces a non-unitary evolution. We apply this idea to the BCS model and study fluctuation around the mean-field average. We find that, dynamics of the thermalization influences the equilibrium besides the non-unitary evolution, and the resulting equilibrium state is no longer the canonical one. The pseudogap phenomenon can exist in this model.

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Lei Gu. 2011-01-20. Fluctuation induced non-canonical BCS states: a mechanism for pseudogap. https://arxiv.org/abs/1101.0247

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