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Title: Electron heating in the conduction band of insulators irradiated by ultrashort laser pulses

Abstract

We investigate the theoretical problem of electron heating in the conduction band of wide band gap insulators and semiconductors induced by intense femto-second Ti:Sapphire laser pulses. We analyze in detail the heating mechanism due to the sequence of direct interbranch transitions in the conduction band, which has been shown to be of crucial importance in previous work. This analysis is fulfilled by resolving the time dependant Schroedinger equation (TDSE) in a basis of Bloch functions for the CsI crystal. The field is represented semiclassically and the laser-electron interaction is treated in the dipole approximation. The presented approaches are based on a one-active electron approximation. First the TDSE is solved in a basis of Bloch functions, in one dimension, the influence of laser and crystal parameters on the electron spectra is studied. The electron transfer from the lower conduction band to the higher one is already effective at intensity of 3x10{sup 12} W/cm{sup 2}. Then the problem is solved in three dimension. The electron spectra is consistent with the experimental results, we note in particular the presence of a large plateau at intensities of the order of the terawatt per square centimeter.

Authors:
; ;  [1];  [2];  [1];  [3]
  1. Centre des Lasers Intenses et Applications, UMR5107 CNRS-Universite de Bordeaux I-CEA, Universite de Bordeaux I, 33405 Talence Cedex (France)
  2. Physics Department, Moscow State University, Vorob'evy Gory, Moscow 119992 (Russian Federation)
  3. (Russian Federation)
Publication Date:
OSTI Identifier:
20853972
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 74; Journal Issue: 23; Other Information: DOI: 10.1103/PhysRevB.74.235215; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; CESIUM IODIDES; CRYSTALS; DIPOLES; ELECTRON SPECTRA; ELECTRON TRANSFER; ELECTRONS; HEATING; IRRADIATION; PULSES; SCHROEDINGER EQUATION; SEMICONDUCTOR LASERS; SEMICONDUCTOR MATERIALS

Citation Formats

Bachau, H., Belsky, A. N., Martin, P., Vasil'ev, A. N., Yatsenko, B. N., and Scobeltsyn Institute of Nuclear Physics, Moscow State University, Vorob'evy Gory, Moscow 119992. Electron heating in the conduction band of insulators irradiated by ultrashort laser pulses. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.74.235215.
Bachau, H., Belsky, A. N., Martin, P., Vasil'ev, A. N., Yatsenko, B. N., & Scobeltsyn Institute of Nuclear Physics, Moscow State University, Vorob'evy Gory, Moscow 119992. Electron heating in the conduction band of insulators irradiated by ultrashort laser pulses. United States. doi:10.1103/PHYSREVB.74.235215.
Bachau, H., Belsky, A. N., Martin, P., Vasil'ev, A. N., Yatsenko, B. N., and Scobeltsyn Institute of Nuclear Physics, Moscow State University, Vorob'evy Gory, Moscow 119992. Fri . "Electron heating in the conduction band of insulators irradiated by ultrashort laser pulses". United States. doi:10.1103/PHYSREVB.74.235215.
@article{osti_20853972,
title = {Electron heating in the conduction band of insulators irradiated by ultrashort laser pulses},
author = {Bachau, H. and Belsky, A. N. and Martin, P. and Vasil'ev, A. N. and Yatsenko, B. N. and Scobeltsyn Institute of Nuclear Physics, Moscow State University, Vorob'evy Gory, Moscow 119992},
abstractNote = {We investigate the theoretical problem of electron heating in the conduction band of wide band gap insulators and semiconductors induced by intense femto-second Ti:Sapphire laser pulses. We analyze in detail the heating mechanism due to the sequence of direct interbranch transitions in the conduction band, which has been shown to be of crucial importance in previous work. This analysis is fulfilled by resolving the time dependant Schroedinger equation (TDSE) in a basis of Bloch functions for the CsI crystal. The field is represented semiclassically and the laser-electron interaction is treated in the dipole approximation. The presented approaches are based on a one-active electron approximation. First the TDSE is solved in a basis of Bloch functions, in one dimension, the influence of laser and crystal parameters on the electron spectra is studied. The electron transfer from the lower conduction band to the higher one is already effective at intensity of 3x10{sup 12} W/cm{sup 2}. Then the problem is solved in three dimension. The electron spectra is consistent with the experimental results, we note in particular the presence of a large plateau at intensities of the order of the terawatt per square centimeter.},
doi = {10.1103/PHYSREVB.74.235215},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 23,
volume = 74,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
  • No abstract prepared.
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