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Diagrammatic Determinantal methods: projective schemes and applications to the Hubbard-Holstein model

F. F. Assaad·T. C. Lang
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Abstract

We extend the weak-coupling diagrammatic determinantal algorithm to projective schemes as well as to the inclusion of phonon degrees of freedom. The projective approach provides a very efficient algorithm to access zero temperature properties. To implement phonons, we integrate them out in favor of a retarded density-density interaction and simulate the resulting purely electronic action with the weak-coupling diagrammatic determinantal algorithm. Both extensions are tested within the dynamical mean field approximation for the Hubbard and Hubbard-Holstein models.

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F. F. Assaad, T. C. Lang. 2007-07-24. Diagrammatic Determinantal methods: projective schemes and applications to the Hubbard-Holstein model. https://doi.org/10.1103/physrevb.76.035116

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