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arXiv · 2012.00604

Dual nature of localized phase defects in the In/Si(111) atomic wire array: impurities and short topological solitons

Abdus Samad Razzaq·Sun Kyu Song·Tae-Hwan Kim·Han Woong Yeom·Stefan Wippermann
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Abstract

We demonstrate the existence of atomically-sized topological solitons in a quasi one-dimensional charge density wave system: indium atomic wires on Si(111). Performing joint scanning tunneling microscopy and density-functional calculations, we show that the Si(111)-(8x2)In surface features two conceptually different types of abrupt phase flip structures. One is caused by In adatoms and is, hence, non-solitonic in nature. The other one is an abrupt left-chiral soliton.

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Abdus Samad Razzaq, Sun Kyu Song, Tae-Hwan Kim, Han Woong Yeom, Stefan Wippermann. 2020-12-01. Dual nature of localized phase defects in the In/Si(111) atomic wire array: impurities and short topological solitons. https://arxiv.org/abs/2012.00604

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