結晶の外形不安定性と形態形成のシミュレーション(<小特集>結晶成長における物質・熱輸送

抄録

When the crystal is growing under the control of diffusion field, the moving interface shows the morphological instability, and that leads to the variety of pattern formation. To realize and study the instability numerically, some simple models are introduced for the interface evolution. Simulation of the Kuramoto-Sivashinsky equation for the unstable step realizes and explains the spatio-temporal chaos observed in the lattice-gas Monte Carlo simulation. Simulation of the geometrical model revealed the importance of crystalline anisotropy in the stabilization of dendritic tip. The realistic aspect of long range correlation in the interface motion mediated by the diffusion field can be exemplified in the more complicated boundary element integration simulation for the dendritic growth. The pattern selection is understood as well as the importance of the capillary anisotropy.