Theoretical Study of Crystal Growth Hysteresis and Catastrophe induced by Impurities

Abstract

  Crystal growth hysteresis and catastrophe are remarkable phenomena induced by impurities. We clarified the fundamental mechanism based on a mean field theory. The mean field theory, however, is too simplified to consider actual crystal growth situations such as non-uniform step spacing and advancing velocities, random impurity adsorption and desorption, and their time fluctuations. To simulate such realistic situations, we developed a numerical scheme based on a phase-field model. We succeeded to reproduce the growth hysteresis and catastrophic behavior as predicted by the mean field theory.

  In this report, I outline a series of our theoretical studies relating to the crystal growth hysteresis and catastrophe. I also suggest our numerical scheme as a powerful tool to investigate other impurity-induced crystal growth phenomena.