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Theory of many-fermion systems II: The case of Coulomb interactions

D. Belitz·F. Evers·T. R. Kirkpatrick
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Abstract

In a recent paper (cond-mat/9703164) a general field-theoretical description of many-fermion systems with short-ranged interactions has been developed. Here we extend this theory to the case of disordered electrons interacting via a Coulomb potential. A detailed discussion is given of the Ward identity that controls the soft modes in the system, and the generalized nonlinear sigma model for the Coulombic case is derived and discussed.

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D. Belitz, F. Evers, T. R. Kirkpatrick. 1999-08-31. Theory of many-fermion systems II: The case of Coulomb interactions. https://doi.org/10.1103/physrevb.58.9710

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