Effect of Atomic-Temperature Dependence of the Electron–Phonon Coupling in Two-Temperature Model

Autor: Fedor Akhmetov, Nikita Medvedev, Igor Makhotkin, Marcelo Ackermann, Igor Milov
Přispěvatelé: XUV Optics, MESA+ Institute
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Materials, 15(15):5193. MDPI
Materials; Volume 15; Issue 15; Pages: 5193
Materials 15(15), 5193 (2022). doi:10.3390/ma15155193
ISSN: 1996-1944
DOI: 10.3390/ma15155193
Popis: Materials 15(15), 5193 (2022). doi:10.3390/ma15155193
Ultrafast laser irradiation of metals can often be described theoretically with the two-temperature model. The energy exchange between the excited electronic system and the atomic one is governed by the electron–phonon coupling parameter. The electron–phonon coupling depends on both, the electronic and the atomic temperature. We analyze the effect of the dependence of the electron–phonon coupling parameter on the atomic temperature in ruthenium, gold, and palladium. It is shown that the dependence on the atomic temperature induces nonlinear behavior, in which a higher initial electronic temperature leads to faster electron–phonon equilibration. Analysis of the experimental measurements of the transient thermoreflectance of the laser-irradiated ruthenium thin film allows us to draw some, albeit indirect, conclusions about the limits of the applicability of the different coupling parametrizations.
Published by MDPI, Basel
Databáze: OpenAIRE