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arXiv · 1908.08957

Coupled electron-impurity and electron-phonon systems as trivial non-Fermi liquids

Donovan Buterakos·Sankar Das Sarma
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Abstract

We consider an electron gas, both in two (2D) and three (3D) dimensions, interacting with quenched impurities and phonons within leading order finite-temperature many body perturbation theories, calculating the electron self-energies, spectral functions, and momentum distribution functions at finite temperatures. The resultant spectral function is in general highly non-Lorentzian, indicating that the system is not a Fermi liquid in the usual sense. The calculated momentum distribution function cannot be approximated by a Fermi function at any temperature, providing a rather simple example of a non-Fermi liquid with well-understood properties.

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Donovan Buterakos, Sankar Das Sarma. 2019-08-23. Coupled electron-impurity and electron-phonon systems as trivial non-Fermi liquids. https://doi.org/10.1103/physrevb.100.235149

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