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, and J. G. Hou

Phys. Rev. Lett. 106, 026801 – Published 13 January 2011

Abstract

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 $\sim 60 meV$ , smaller than one-half of the band gap of $\sim 200 meV$ . 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.

Received 2 August 2010

DOI:https://doi.org/10.1103/PhysRevLett.106.026801

Authors & Affiliations

Hui Zhang¹, Jin-Ho Choi², Yang Xu¹, Xiuxia Wang¹, Xiaofang Zhai¹, Bing Wang¹, Changgan Zeng^1,3,*, Jun-Hyung Cho^2,†, Zhenyu Zhang^3,4, and J. G. Hou^1,3

¹Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, University of Science and Technology of China, 96 JinZhai Road, Hefei, Anhui 230026, China
²Department of Physics, Hanyang University, 17 Haengdang-Dong, Seongdong-Ku, Seoul 133-791, Korea
³ICQD/HFNL, University of Science and Technology of China, Hefei, Anhui, 230026, China
⁴Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA