アモルファスGeにおける構造緩和過程の 分子動力学法による解析

抄録

Structural relaxation of amorphous germanium has been examined by molecular dynamics simulations based on the empirical Tersoff interatomic potential. Although the Tersoff potential overestimated both the melting and glass transition temperatures, it was found that this potential can reproduce the behavior of structural relaxation. The potential energy decreased with thermal annealing below the glass transition temperature, but it sometimes increased during structural relaxation. The mean square displacement of atoms also increased at the corresponding period. These changes were attributed to the cooperative atomic motion during structure relaxation. Atomic trajectories revealed that structural changes are induced by spatially- and temporally-inhomogeneous atomic motions: atomic mobile and immobile regions coexisted during structural relaxation.