Nonequilibrium sum rules for the retarded self-energy of strongly correlated electrons
نویسندگان
چکیده
We derive the first two moment sum rules of the conduction electron retarded self-energy for both the Falicov–Kimball model and the Hubbard model coupled to an external spatially uniform and time-dependent electric field this derivation also extends the known nonequilibrium moment sum rules for the Green functions to the third moment . These sum rules are used to further test the accuracy of nonequilibrium solutions to the many-body problem; for example, we illustrate how well the self-energy sum rules are satisfied for the Falicov–Kimball model in infinite dimensions and placed in a uniform electric field turned on at time t=0. In general, the self-energy sum rules are satisfied to a significantly higher accuracy than the Green function sum rules.
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