The Interaction of Ultrashort Laser Pulses with Semiconductors
Abstract
The interaction of ultrashort intense laser pulses with Si and GaAs are investigated via simulations of the coupled electron-ion dynamics using the nonadiabatic tight-binding electron-ion dynamics scheme (TED). Both semi-empirical orthogonal tight-binding and density-functional based nonorthogonal tight-binding models are used. The external radiation field is introduced into the Hamiltonian through a time-dependent Peierls substitution. Results will be presented on the photoexcitation of coherent phonons in bulk materials as well as the results of intense ultrashort pulse interactions with surfaces leading to atomic motion far from equilibrium, including atoms ejected from the surface. Changes in the imaginary part of the dielectric function and the density of states are monitored and will be presented along with snapshots of animations showing modifications to the surface. Results will be compared to the available experimental data. This work was performed under the auspices of the U. S. Department of Energy by the University of California Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48. Partial support from NATO under Contract No. CRG 941028 is gratefully acknowledged.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARL22003T