**Simulations of copper single crystals subjected to rapid shear**

A Higginbotham and EM Bringa and J Marian and N Park and M Suggit and JS Wark, JOURNAL OF APPLIED PHYSICS, 109, 063530 (2011).

DOI: 10.1063/1.3560912

We report on nonequilibrium molecular dynamics simulations of single
crystals of copper experiencing rapid shear strain. A model system, with
periodic boundary conditions, which includes a single dislocation dipole
is subjected to a total shear strain of close to 10% on time-scales
ranging from the instantaneous to 50 ps. When the system is strained on
a time-scale short compared with a phonon period, the initial total
applied shear is purely elastic, and the eventual temperature rise in
the system due to the subsequent plastic work can be determined from the
initial elastic strain energy. The rate at which this plastic work
occurs, and heat is generated, depends on the dislocation velocity,
which itself is a function of shear stress. A determination of the
stress-dependence of the dislocation velocity allows us to construct a
simple analytic model for the temperature rise in the system as a
function of strain rate, and this model is found to be in good agreement
with the simulations. For the effective dislocation density within the
simulations, 7: 8 x 10(11) cm(-2), we find that applying the total shear
strain on time-scales of a few tens of picoseconds greatly reduces the
final temperature. We discuss these results in the context of the
growing interest in producing high pressure, solid-state matter, by
quasi-isentropic (rather than shock) compression. (C) 2011 American
Institute of Physics. **doi:10.1063/1.3560912**

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