Effect of temperature on the dynamics of energetic displacement cascades: A molecular dynamics study

Abstract

Molecular dynamics simulations of 3-keV displacement cascades in Cu at temperatures of 0, 300, 500, and 700 K have been performed using the Gibson II potential. Most atomic displacements occur in the quasimolten core region that develops at t\ensuremath{\sim}0.5 ps and persists for several ps. The size and lifetime of the molten regions increase with ambient temperature, which results in a fourfold increase in atomic mixing between 0 to 700 K and a decrease in defect production. The instantaneous diffusion coefficients in the cascade melt are in close agreement with those in the equilibrium liquid.