Mean Green's function of the Anderson model at weak disorder with an infra-red cut-off

Gilles Poirot

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Mean Green's function of the Anderson model at weak disorder with an infra-red cut-off

Gilles Poirot

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Abstract

We develop a polymer expansion with large/small field conditions for the mean resolvent of a weakly disordered system. Then we show that we can apply our result to a two-dimensional model, for energies outside the unperturbed spectrum or in the free spectrum provided the potential has an infra-red cut-off. This leads to an asymptotic expansion for the density of states. We believe this is an important first step towards a rigourous analysis of the density of states in the free spectrum of a random Schrödinger operator at weak disorder.

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Gilles Poirot. 1997-02-12. Mean Green's function of the Anderson model at weak disorder with an infra-red cut-off. https://arxiv.org/abs/cond-mat/9702111

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