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arXiv · 2007.09378

Ultrafast dynamics of electron-phonon coupling in a metal

Choongyu Hwang·Wentao Zhang·Koshi Kurashima·Robert Kaindl·Tadashi Adachi·Alessandra Lanzara
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Abstract

In the past decade, the advent of time-resolved spectroscopic tools has provided a new ground to explore fundamental interactions in solids and to disentangle degrees of freedom whose coupling leads to broad structures in the frequency domain. Time- and angle-resolved photoemission spectroscopy (tr-ARPES) has been utilized to directly study the relaxation dynamics of a metal in the presence of electron-phonon coupling. The effect of photo-excitations on the real and imaginary part of the self-energy as well as the time scale associated with different recombination processes are discussed. In contrast to a theoretical model, the phonon energy does not set a clear scale governing quasiparticle dynamics, which is also different from the results observed in a superconducting material. These results point to the need for a more complete theoretical framework to understand electron-phonon interaction in a photo-excited state.

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Choongyu Hwang, Wentao Zhang, Koshi Kurashima, Robert Kaindl, Tadashi Adachi, Alessandra Lanzara. 2020-07-18. Ultrafast dynamics of electron-phonon coupling in a metal. https://doi.org/10.1209/0295-5075/126/57001

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