Atomic structure, energetics, and dynamics of topological solitons in Indium chains on Si(111) surfaces

Hui Zhang, Jin-Ho Choi, Yang Xu, Xiuxia Wang, Xiaofang Zhai, Bing Wang, Changgan Zeng, Jun-Hyung Cho, Zhenyu Zhang, J. G. Hou

Published 2010-09-06, updated 2011-04-12Version 3

Based on scanning tunneling microscopy and first-principles theoretical studies, we characterize the precise atomic structure of a topological soliton in In chains grown on Si(111) surfaces. Variable-temperature measurements of the soliton population allow us to determine the soliton formation energy to be ~60 meV, smaller than one half of the band gap of ~200 meV. Once created, these solitons have very low mobility, even though the activation energy is only about 20 meV; the sluggish nature is attributed to the exceptionally low attempt frequency for soliton migration. We further demonstrate local electric field-enhanced soliton dynamics.