Melting kinetics of confined systems at the nanoscale

Sharp, I. D.; Xu, Q.; Yuan, C. W.; Yi, D. O.; Liao, C. Y.; Glaeser, A. M.; Minor, A. M.; Beeman, J. W.; Ridgway, M. C.; Kluth, P.; Ager, J. W.; Chrzan, D. C.; Haller, E. E.

Melting kinetics of confined systems at the nanoscale

Date

2007

Authors

Abstract

In situ electron diffraction measurements of silica-embedded Ge nanocrystals reveal a melting/solidification hysteresis of 470 K which is approximately symmetric about the bulk melting point. This surprising behavior, which is thought to be impossible in bulk systems, is well described by a simple, classical thermodynamic model. Surface pre-melting, which occurs for materials with free surfaces, is suppressed by the presence of the host matrix, thereby allowing both kinetic supercooling and kinetic superheating of the embedded nanocrystals.