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Self-energy-functional approach to systems of correlated electrons

Michael Potthoff
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Abstract

The grand potential of a system of interacting electrons is considered as a stationary point of a self-energy functional. It is shown that a rigorous evaluation of the functional is possible for self-energies that are representable within a certain reference system. The variational scheme allows to construct new non-perturbative and thermodynamically consistent approximations. Numerical results illustrate the practicability of the method.

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Michael Potthoff. 2003-01-10. Self-energy-functional approach to systems of correlated electrons. https://doi.org/10.1140/epjb%2Fe2003-00121-8

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