Open AccessAtomic Imaging of Electrically Switchable Striped Domains in β ′‐In 2 Se 3
Author(s) -
Chen Zhi,
Fu Wei,
Wang Lin,
Yu Wei,
Li Haohan,
Tan Clement Kok Yong,
Abdelwahab Ibrahim,
Shao Yan,
Su Chenliang,
Sun Mingzi,
Huang Bolong,
Loh Kian Ping
Publication year - 2021
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202100713
Subject(s) - ferroelectricity , materials science , van der waals force , nanoscopic scale , optoelectronics , piezoresponse force microscopy , subthreshold swing , indium , nanotechnology , condensed matter physics , quantum tunnelling , transistor , voltage , dielectric , field effect transistor , chemistry , physics , organic chemistry , molecule , quantum mechanics
Abstract 2D ferroelectricity in van‐der‐Waals‐stacked materials such as indium selenide (In 2 Se 3 ) 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 In 2 Se 3 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 ′‐In 2 Se 3 , and the reconfiguration of these domains are directly visualized using STM. The room‐temperature surface of β ′‐In 2 Se 3 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.