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Title: Quantum Molecular Dynamics Simulations for the Nonmetal-to-Metal Transition in Fluid Helium

Abstract

We have performed quantum molecular dynamics simulations for dense helium to study the nonmetal-to-metal transition at high pressures. We present new results for the equation of state and the Hugoniot curve in the warm dense matter region. The optical conductivity is calculated via the Kubo-Greenwood formula from which the dc conductivity is derived. The nonmetal-to-metal transition is identified at about 1 g/cm{sup 3}. We compare with experimental results as well as with other theoretical approaches, especially with predictions of chemical models.

Authors:
; ; ; ;  [1];  [2]
  1. Universitaet Rostock, Institut fuer Physik, D-18051 Rostock (Germany)
  2. (United States)
Publication Date:
OSTI Identifier:
20951349
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevLett.98.190602; (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; COMPARATIVE EVALUATIONS; EQUATIONS OF STATE; HELIUM; MOLECULAR DYNAMICS METHOD; SIMULATION

Citation Formats

Kietzmann, Andre, Holst, Bastian, Redmer, Ronald, Desjarlais, Michael P., Mattsson, Thomas R., and Pulsed Power Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87185-1186. Quantum Molecular Dynamics Simulations for the Nonmetal-to-Metal Transition in Fluid Helium. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.190602.
Kietzmann, Andre, Holst, Bastian, Redmer, Ronald, Desjarlais, Michael P., Mattsson, Thomas R., & Pulsed Power Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87185-1186. Quantum Molecular Dynamics Simulations for the Nonmetal-to-Metal Transition in Fluid Helium. United States. doi:10.1103/PHYSREVLETT.98.190602.
Kietzmann, Andre, Holst, Bastian, Redmer, Ronald, Desjarlais, Michael P., Mattsson, Thomas R., and Pulsed Power Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87185-1186. Fri . "Quantum Molecular Dynamics Simulations for the Nonmetal-to-Metal Transition in Fluid Helium". United States. doi:10.1103/PHYSREVLETT.98.190602.
@article{osti_20951349,
title = {Quantum Molecular Dynamics Simulations for the Nonmetal-to-Metal Transition in Fluid Helium},
author = {Kietzmann, Andre and Holst, Bastian and Redmer, Ronald and Desjarlais, Michael P. and Mattsson, Thomas R. and Pulsed Power Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87185-1186},
abstractNote = {We have performed quantum molecular dynamics simulations for dense helium to study the nonmetal-to-metal transition at high pressures. We present new results for the equation of state and the Hugoniot curve in the warm dense matter region. The optical conductivity is calculated via the Kubo-Greenwood formula from which the dc conductivity is derived. The nonmetal-to-metal transition is identified at about 1 g/cm{sup 3}. We compare with experimental results as well as with other theoretical approaches, especially with predictions of chemical models.},
doi = {10.1103/PHYSREVLETT.98.190602},
journal = {Physical Review Letters},
number = 19,
volume = 98,
place = {United States},
year = {Fri May 11 00:00:00 EDT 2007},
month = {Fri May 11 00:00:00 EDT 2007}
}
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