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An effective theory for conductance by symmetry breaking

Sebastiao Correia·Janos Polonyi·Jean Richert
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Abstract

An effective theory is suggested for the particle-anti particle and the particle-particle modes of strongly disordered electron systems. The effective theory is studied in the framework of the saddle point expansion and found to support a vacuum which is not invariant under translations in imaginary time. The Goldstone bosons of this symmetry breaking generate a pole in the density-density correlation function. The condensate of the auxiliary field corresponding to the particle-particle channel produces conductivity without relying on the long range fluctuations. The results are obtained for $d>1$.

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Sebastiao Correia, Janos Polonyi, Jean Richert. 2000-10-16. An effective theory for conductance by symmetry breaking. https://arxiv.org/abs/cond-mat/0001053

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