Commensurate-incommensurate transition and domain wall dynamics of adsorbed overlayers on a honeycomb substrate
journal contributionposted on 19.01.2018, 09:46 authored by Ken R. Elder, C.V. Achim, E. Granato, S.C. Ying, Tapio Ala-NissilaTapio Ala-Nissila
© EPLA, 2016.We introduce an effective one-mode phase-field crystal model for studying the commensurate-incommensurate transition and domain wall dynamics of the ( √ 3×√3)R30 phase found in systems such as Xe/Pt(111), or Xe and Kr on graphite. The model allows us to study large systems where the domain walls can be separated over large macroscopic distances and at the same time incorporate the microscopic details of the domain wall structures. The resulting phase diagram shows that an intermediate stripe incommensurate phase always separates the commensurate phase from the honeycomb incommensurate phases. The energy of the domain wall crossing is investigated. We also find that near a step edge, the domain walls tend to align perpendicularly to the step edge, in agreement with recent experimental observations.
This work was supported by the Sao Paulo Research Foundation (FAPESP, Grant No. 2014/15372-3) (E.G.), the CNPq (Brazi) (E.G.), the Watson Institute at Brown University under a Brazil Collaborative Grant (S.-C.Y.) and the National Science Foundation under Grant No. DMR-1506634 (K.R.E.) . CVA acknowledges financial support from CRHIAM-FONDAPCONICYT Project 15130015. T.A-N. acknowledges partial support from Aalto Science Institute and the Academy of Finland though grants nos. 251748 and 284621.
- Mathematical Sciences