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arXiv · 2505.08081

Electron-phonon coupling in correlated materials: insights from the Hubbard-Holstein model

Jennifer Coulter·Andrew J. Millis
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Abstract

Dynamical mean-field theory computations of the electron self energy of the Hubbard-Holstein model as a function of electron-phonon and electron-electron interactions are analyzed to gain insight into the dependence of electron-phonon couplings on correlation strength in quantum materials. We find that the electron-phonon interaction is strongly suppressed by electronic correlations, while electron-electron correlation effects at Fermi liquid scales are only weakly modified by coupling to phonons, with phonon-induced modifications most evident at high frequencies on the order of the electronic bandwidth. Implications for beyond-density functional theories of the electron-phonon interaction are discussed.

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Jennifer Coulter, Andrew J. Millis. 2025-05-12. Electron-phonon coupling in correlated materials: insights from the Hubbard-Holstein model. https://doi.org/10.1103/3qk3-py1n

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