# Two-speed phase dynamics in Si111 7x7-1x1 phase transition - Condensed Matter > Materials Science

Abstract: We propose a natural two-speed model for the phase dynamics of Si1117$\times$7 phase transition to high temperature unreconstructed phase. Weformulate the phase dynamics by using phase-field method and adaptive meshrefinement. Our simulated results show that a 7$\times$7 island decays with itsshape kept unchanged, and its area decay rate is shown to be a constantincreasing with its initial area. LEEM experiments concerned are explained,which confirms that the dimer chains and corner holes are broken first in thetransition, and then the stacking fault is remedied slowly. This phase-fieldmethod is a reliable approach to phase dynamics of surface phase transitions.

Author: Ye-Chuan Xu, Bang-Gui Liu

Source: https://arxiv.org/