Time scale for point-defect equilibration in nanostructures

Millett, Paul C.; Wolf, Dieter; Desai, Tapan; Yamakov, Vesselin
October 2008
Applied Physics Letters;10/20/2008, Vol. 93 Issue 16, p161902
Academic Journal
Molecular dynamics simulations of high-temperature annealing are performed on nanostructured materials enabling direct observation of vacancy emission from planar defects (i.e., grain boundaries and free surfaces) to populate the initially vacancy-free grain interiors on a subnanosecond time scale. We demonstrate a universal time-length scale correlation that governs these re-equilibration processes, suggesting that nanostructures are particularly stable against perturbations in their point-defect concentrations, caused for example by particle irradiation or temperature fluctuations.


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