Atomic Imaging of Electrically Switchable Striped Domains in β′-In2Se3

Zhi Chen, Wei Fu, Lin Wang, Wei Yu, Haohan Li, Clement Kok Yong Tan, Ibrahim Abdelwahab, Yan Shao, Chenliang Su, Mingzi Sun, Bolong Huang, Kian Ping Loh

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

2D ferroelectricity in van-der-Waals-stacked materials such as indium selenide (In2Se3) has attracted interests because the ferroelectricity is robust even in ultrathin layers, which is useful for the miniaturization of ferroelectric field effect transistors. To implement In2Se3 in nanoscale ferroelectric devices, an understanding of the domain structure and switching dynamics in the 2D limit is essential. In this study, a biased scanning tunnelling microscopy (STM) tip is used to locally switch polarized domains in β′-In2Se3, and the reconfiguration of these domains are directly visualized using STM. The room-temperature surface of β′-In2Se3 breaks into 1D nanostriped domains, which changes into a zig-zag striped domains of β″ phase at low temperatures. These two types of domains can coexist, and by applying a tip-sample bias, they can be interchangeably switched locally, showing volatile or nonvolatile like behavior depending on the threshold voltage applied. An atomic model is proposed to explain the switching mechanism based on tip-induced flexoelectric effect and the ferroelastic switching between β′ and β″ phases.

Original languageEnglish
Article number2100713
JournalAdvanced Science
Volume8
Issue number17
DOIs
Publication statusPublished - 8 Sep 2021

Keywords

  • antiferroelectrics
  • ferroelectrics
  • indium selenide
  • phase changes
  • scanning tunneling microscopy

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Chemical Engineering(all)
  • Materials Science(all)
  • Biochemistry, Genetics and Molecular Biology (miscellaneous)
  • Engineering(all)
  • Physics and Astronomy(all)

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