Crystalline symmetry and the melt-growth kinetics of solid-liquid interface

TL;DR

This paper derives an analytical expression for the kinetic coefficients governing solid-liquid interface growth, revealing anisotropy due to crystalline symmetry, and validates it against existing theories and molecular dynamics simulations.

Contribution

It introduces a Ginzburg-Landau based analytical model for interface kinetics that accounts for anisotropy from crystalline symmetry, aligning well with prior theories and simulations.

Findings

Analytical expression matches Mikheev-Chernov theory

Results agree with molecular dynamics simulations

Reveals origin of anisotropy in interfacial kinetics

Abstract

One of the important factors governing the growth morphology of materials is the interface kinetic coefficient \mu, which is the proportionality constant between the velocity of solid-liquid interface and undercooling. We employ Ginzburg-Landau (GL) free energy functional to derive an analytical expression of kinetic coefficients. The anisotropy of kinetic coefficients naturally arise from the broken symmetry at the solid-liquid interface for various crystalline orientations. The analytical expression of kinetic coefficients is compared to Mikheev-Chernov theory [J. Cryst. Growth 112, 591 (1991)] derived from hydrodynamic equations. In addition, we use equilibrium density wave profiles to evaluate kinetic coefficients and compare them with that from MD simulations. Our results are in good agreement with Mikheev-Chernov theory and MD simulations and shed lights on a possible origin of anisotropy of interfacial kinetics.