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arXiv · 1602.04195

Density matrix embedding theory for interacting electron-phonon systems

Barbara Sandhoefer·Garnet Kin-Lic Chan
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Abstract

We describe the extension of the density matrix embedding theory (DMET) framework to coupled interacting fermion-boson systems. This provides a frequency-independent, entanglement embedding formalism to treat bulk fermion-boson problems. We illustrate the concepts within the context of the one-dimensional Hubbard-Holstein model, where the phonon bath states are obtained from the Schmidt decomposition of a self-consistently adjusted coherent state. We benchmark our results against accurate density matrix renormalization group calculations.

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Barbara Sandhoefer, Garnet Kin-Lic Chan. 2016-02-12. Density matrix embedding theory for interacting electron-phonon systems. https://doi.org/10.1103/physrevb.94.085115

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