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Ward type identities for the 2d Anderson model at weak disorder

Jacques Magnen·Gilles Poirot·Vincent Rivasseau
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Abstract

Using the particular momentum conservation laws in dimension d=2, we can rewrite the Anderson model in terms of low momentum long range fields, at the price of introducing electron loops. The corresponding loops satisfy a Ward type identity, hence are much smaller than expected. This fact should be useful for a study of the weak-coupling model in the middle of the spectrum of the free Hamiltonian.

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Jacques Magnen, Gilles Poirot, Vincent Rivasseau. 1998-01-21. Ward type identities for the 2d Anderson model at weak disorder. https://doi.org/10.1023/b%3Ajoss.0000026737.08422.fd

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