Topological solitons versus nonsolitonic phase defects in a quasi-one-dimensional charge-density wave.
We investigated phase defects in a quasi-one-dimensional commensurate charge-density wave (CDW) system, an In atomic wire array on Si(111), using low temperature scanning tunneling microscopy. The unique fourfold degeneracy of the CDW state leads to various phase defects, among which intrinsic solitons are clearly distinguished. The solitons exhibit a characteristic variation of the CDW amplitude with a coherence length of about 4 nm, as expected from the electronic structure, and a localized electronic state within the CDW gap. While most of the observed solitons are trapped by extrinsic defects, moving solitons are also identified and their novel interaction with extrinsic defects is disclosed.
Center for Low Dimensional Electronic Symmetry and Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea. taehwan@postech.ac.kr
Tae-Hwan
TH
Kim
Han Woong
HW
Yeom