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Title: Molecular dynamics simulations of coherent optical photon emission from shock waves in crystals

Abstract

We have previously predicted that coherent electromagnetic radiation in the 1-100 THz frequency range can be generated in crystalline polarizable materials when subject to a shock wave or solitonlike propagating excitation [E. J. Reed et al., Phys. Rev. Lett. 96, 013904 (2006)]. In this work, we present analysis and molecular dynamics simulations of shock waves in crystalline NaCl which expand upon this prediction. We demonstrate that the coherent polarization currents responsible for the effect are generated by a nonresonant, nonlinear effect that occurs at the shock front. We consider the effect of thermal noise and various shock pressures on the coherent polarization currents and find that the amplitude generally increases with increasing shock pressure and decreasing material temperature. Finally, we present calculations of the amplitude and distribution of emitted radiation showing that the radiation can be directed or undirected under various realistic conditions of the shape of the shock front.

Authors:
 [1];  [2]; ;  [3];  [1]
  1. Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)
  2. (United States)
  3. Center for Materials Science and Engineering and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
Publication Date:
OSTI Identifier:
20957832
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.75.174302; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; CRYSTALS; ELECTROMAGNETIC RADIATION; EXCITATION; FREQUENCY RANGE; MOLECULAR DYNAMICS METHOD; NOISE; NONLINEAR PROBLEMS; PHOTON EMISSION; POLARIZATION; SHOCK WAVES; SIMULATION; SODIUM CHLORIDES

Citation Formats

Reed, Evan J., Center for Materials Science and Engineering and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, Soljacic, Marin, Joannopoulos, J. D., and Gee, Richard. Molecular dynamics simulations of coherent optical photon emission from shock waves in crystals. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.174302.
Reed, Evan J., Center for Materials Science and Engineering and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, Soljacic, Marin, Joannopoulos, J. D., & Gee, Richard. Molecular dynamics simulations of coherent optical photon emission from shock waves in crystals. United States. doi:10.1103/PHYSREVB.75.174302.
Reed, Evan J., Center for Materials Science and Engineering and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, Soljacic, Marin, Joannopoulos, J. D., and Gee, Richard. Tue . "Molecular dynamics simulations of coherent optical photon emission from shock waves in crystals". United States. doi:10.1103/PHYSREVB.75.174302.
@article{osti_20957832,
title = {Molecular dynamics simulations of coherent optical photon emission from shock waves in crystals},
author = {Reed, Evan J. and Center for Materials Science and Engineering and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Soljacic, Marin and Joannopoulos, J. D. and Gee, Richard},
abstractNote = {We have previously predicted that coherent electromagnetic radiation in the 1-100 THz frequency range can be generated in crystalline polarizable materials when subject to a shock wave or solitonlike propagating excitation [E. J. Reed et al., Phys. Rev. Lett. 96, 013904 (2006)]. In this work, we present analysis and molecular dynamics simulations of shock waves in crystalline NaCl which expand upon this prediction. We demonstrate that the coherent polarization currents responsible for the effect are generated by a nonresonant, nonlinear effect that occurs at the shock front. We consider the effect of thermal noise and various shock pressures on the coherent polarization currents and find that the amplitude generally increases with increasing shock pressure and decreasing material temperature. Finally, we present calculations of the amplitude and distribution of emitted radiation showing that the radiation can be directed or undirected under various realistic conditions of the shape of the shock front.},
doi = {10.1103/PHYSREVB.75.174302},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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