Stroboscopic Tests for Thermalization of Electrons in Pump-Probe Experiments

O. P. Matveev, A. M. Shvaika, T. P. Devereaux, and J. K. Freericks

Phys. Rev. Lett. 122, 247402 – Published 19 June 2019

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.

Received 24 August 2018
Revised 20 May 2019

DOI:https://doi.org/10.1103/PhysRevLett.122.247402

Physics Subject Headings (PhySH)

Strongly correlated systems

Nonequilibrium Green's function Photoemission spectroscopy Raman spectroscopy Ultrafast pump-probe spectroscopy

Condensed Matter, Materials & Applied PhysicsGeneral PhysicsAtomic, Molecular & OpticalStatistical Physics & ThermodynamicsParticles & Fields

Authors & Affiliations

O. P. Matveev^1,4, A. M. Shvaika¹, T. P. Devereaux^2,3, and J. K. Freericks⁴

¹Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, Lviv, 79011 Ukraine
²Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
³Stanford Institute for Materials and Energy Sciences (SIMES), SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
⁴Department of Physics, Georgetown University, Washington, DC 20057, USA