Coupling between phase solitons and strain near the commensurate-incommensurate transition

Abstract

Near the commensurate-incommensurate transition the incommensurate phase is characterised by the formation of 'discommensurations' or phase solitons. The authors consider the coupling to an elastic strain along the wavevector describing the modulation. The solitons induce a highly non-homogeneous soliton-like strain. The measurable macroscopic strain is proportional to the phase-soliton density. The transition remains second order in contrast to previous expectations.