体心立方結晶における非線形エネルギー局在振動の探索

抄録

Spatially localized vibration modes in bcc model crystals are investigated numerically. Spatially discreteness of crystal and nonlinearity of atomic interaction support the existence of these localized modes. We construct a hybrid computation method of the molecular dynamics simulation and the iteration method for finding periodic orbit in the phase space. Using the constructed method, we find two types of stationary localized modes in the bcc model crystal: bond-center modes and site-center modes. Frequency of these mode is out of the dispersion band. Structure of these modes in 3D crystal is investigated in detail.