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arXiv · 1808.07944

Stroboscopic Tests for Thermalization of Electrons in Pump/Probe Experiments

O. P. Matveev·A. M. Shvaika·T. P. Devereaux·J. K. Freericks
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Abstract

One of the goals of pump/probe spectroscopies is to determine how electrons relax after they have been driven out of equilibrium. It is challenging to determine how close electrons are to a thermal state solely by fitting their distribution to a Fermi-Dirac distribution. Instead, we propose that one compare the effective temperatures of both fermions and collective bosonic modes (derived from the fermions) to determine the distance from a thermal state. Measurements of effective fermionic and bosonic temperatures can be achieved directly via photoemission and nonresonant Raman scattering. Their difference quantifies the distance from thermal equilibrium.

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O. P. Matveev, A. M. Shvaika, T. P. Devereaux, J. K. Freericks. 2018-08-23. Stroboscopic Tests for Thermalization of Electrons in Pump/Probe Experiments. https://doi.org/10.1103/physrevlett.122.247402

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