On the spectrum of facet crystallization waves at the smooth 4He crystal surface

TL;DR

This paper investigates the spectrum of crystallization waves on smooth 4He crystal surfaces, revealing unique features caused by nonanalytic surface tension behavior, which differ from waves on rough surfaces.

Contribution

It provides the first analysis of facet crystallization wave spectrum and its dependence on wavelength, amplitude, and facet steps for smooth 4He crystal surfaces.

Findings

Distinctive nonanalytic cusp behavior in surface tension influences wave spectrum.

Spectrum depends on wavelength, perturbation amplitude, and facet step distribution.

Differences from conventional waves on rough surfaces are characterized.

Abstract

The wavelike processes of crystallization and melting or crystallization waves are well known to exist at the 4He crystal surface in the rough state. Much less is known about crystallization waves for the 4He crystal surface in the smooth well-faceted state below the roughening transition temperature. To meet the lack, we analyze here the spectrum of facet crystallization waves and its dependence upon the wavelength, perturbation amplitude, and the number of possible facet steps distributed somehow over the wavelength. All the distinctive features of facet crystallization waves from conventional waves at the rough surface result from a nonanalytic cusplike behavior in the angle dependence for the surface tension of smooth crystal facets.