Kinetic roughening-like transition with finite nucleation barrier

TL;DR

This paper demonstrates that a transition in crystal growth modes, similar to kinetic roughening, can occur due to finite nucleation barriers, using analytical models and simulations, rather than solely from barrier vanishing.

Contribution

It introduces a new perspective that kinetic roughening-like transitions can result from finite nucleation barriers, supported by mean field models and kinetic Monte Carlo simulations.

Findings

Transition between smooth and rough growth regimes observed.

Kinetic roughening-like transition can occur at finite nucleation barriers.

Analytic and simulation results support the kinetic effect hypothesis.

Abstract

Recent observations of the growth of protein crystals have identified two different growth regimes. At low supersaturation, the surface of the crystal is smooth and increasing in size due to the nucleation of steps at defects and the subsequent growth of the steps. At high supersaturation, nucleation occurs at many places simultaneously, the crystal surface becomes rough and the growth velocity increases more rapidly with increasing supersaturation than in the smooth regime. Kinetic roughening transitions are typically assumed to be due to the vanishing of the barrier for two-dimension nucleation on the surface of the crystal. We show here, by means of both analytic mean field models and kinetic Monte Carlo simulations that a transition between different growth modes reminiscent of kinetic roughening can also arise as a kinetic effect occurring at finite nucleation barriers.