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Title: Electron-ion coupling in semiconductors beyond Fermi's Golden Rule [On the electron-ion coupling in semiconductors beyond Fermi's Golden Rule]

Abstract

In the present study, a theoretical study of electron-phonon (electron-ion) coupling rates in semiconductors driven out of equilibrium is performed. Transient change of optical coefficients reflects the band gap shrinkage in covalently bonded materials, and thus, the heating of atomic lattice. Utilizing this dependence, we test various models of electron-ion coupling. The simulation technique is based on tight-binding molecular dynamics. Our simulations with the dedicated hybrid approach (XTANT) indicate that the widely used Fermi's golden rule can break down describing material excitation on femtosecond time scales. In contrast, dynamical coupling proposed in this work yields a reasonably good agreement of simulation results with available experimental data.

Authors:
 [1];  [2];  [3];  [4]
  1. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Czech Academy of Sciences, Prague 8 (Czech Republic)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
  3. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
  4. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Polish Academy of Sciences, Krakow (Poland)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1368585
Grant/Contract Number:
AC02-76SF00515; LG15013; LM2015083
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 95; Journal Issue: 1; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Medvedev, Nikita, Li, Zheng, Tkachenko, Victor, and Ziaja, Beata. Electron-ion coupling in semiconductors beyond Fermi's Golden Rule [On the electron-ion coupling in semiconductors beyond Fermi's Golden Rule]. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.95.014309.
Medvedev, Nikita, Li, Zheng, Tkachenko, Victor, & Ziaja, Beata. Electron-ion coupling in semiconductors beyond Fermi's Golden Rule [On the electron-ion coupling in semiconductors beyond Fermi's Golden Rule]. United States. doi:10.1103/PhysRevB.95.014309.
Medvedev, Nikita, Li, Zheng, Tkachenko, Victor, and Ziaja, Beata. Tue . "Electron-ion coupling in semiconductors beyond Fermi's Golden Rule [On the electron-ion coupling in semiconductors beyond Fermi's Golden Rule]". United States. doi:10.1103/PhysRevB.95.014309. https://www.osti.gov/servlets/purl/1368585.
@article{osti_1368585,
title = {Electron-ion coupling in semiconductors beyond Fermi's Golden Rule [On the electron-ion coupling in semiconductors beyond Fermi's Golden Rule]},
author = {Medvedev, Nikita and Li, Zheng and Tkachenko, Victor and Ziaja, Beata},
abstractNote = {In the present study, a theoretical study of electron-phonon (electron-ion) coupling rates in semiconductors driven out of equilibrium is performed. Transient change of optical coefficients reflects the band gap shrinkage in covalently bonded materials, and thus, the heating of atomic lattice. Utilizing this dependence, we test various models of electron-ion coupling. The simulation technique is based on tight-binding molecular dynamics. Our simulations with the dedicated hybrid approach (XTANT) indicate that the widely used Fermi's golden rule can break down describing material excitation on femtosecond time scales. In contrast, dynamical coupling proposed in this work yields a reasonably good agreement of simulation results with available experimental data.},
doi = {10.1103/PhysRevB.95.014309},
journal = {Physical Review B},
number = 1,
volume = 95,
place = {United States},
year = {Tue Jan 31 00:00:00 EST 2017},
month = {Tue Jan 31 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 3works
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