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arXiv · 2310.19143

Quantum-Acoustical Drude Peak Shift

J. Keski-Rahkonen·X. -Y. Ouyang·S. Yuan·A. M. Graf·A. Aydin·E. J. Heller
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Abstract

Quantum acoustics -- a recently developed framework parallel to quantum optics -- establishesa nonperturbative and coherent treatment of the electron-phonon interaction in real space. The quantum-acoustical representation reveals a displaced Drude peak hid ing in plain sight within the venerable Fr\"ohlich model: the optical conductivity exhibits a finite frequency maximum in the far-infrared range and the d.c. conductivity is suppressed. Our results elucidate the origin of the high-temperature absorption peaks in strange or bad metals, revealing that dynamical lattice disorder steers the system towards a non-Drude behavior

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J. Keski-Rahkonen, X. -Y. Ouyang, S. Yuan, A. M. Graf, A. Aydin, E. J. Heller. 2023-10-29. Quantum-Acoustical Drude Peak Shift. https://doi.org/10.1103/physrevlett.132.186303

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