title: Discovery of robust in-plane ferroelectricity in atomic-thick SnTe.
abstract: Stable ferroelectricity with high transition temperature in nanostructures is needed for miniaturizing ferroelectric devices. Here, we report the discovery of the stable in-plane spontaneous polarization in atomic-thick tin telluride (SnTe), down to a 1-unit cell (UC) limit. The ferroelectric transition temperature T(c) of 1-UC SnTe film is greatly enhanced from the bulk value of 98 kelvin and reaches as high as 270 kelvin. Moreover, 2- to 4-UC SnTe films show robust ferroelectricity at room temperature. The interplay between semiconducting properties and ferroelectricity in this two-dimensional material may enable a wide range of applications in nonvolatile high-density memories, nanosensors, and electronics.
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Chang
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Junwei
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Haicheng
authors.initials: H
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Na
authors.initials: N
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Zhao
authors.affiliation: Department of Physics, Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing 100872, China.
authors.forename: Anmin
authors.initials: A
authors.lastname: Zhang
authors.affiliation: Department of Physics, Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing 100872, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Wenhui
authors.initials: W
authors.lastname: Duan
authors.affiliation: Department of Physics, Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing 100872, China. Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China.
authors.forename: Qingming
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Fu
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Qi-Kun
authors.initials: QK
authors.lastname: Xue
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China. xc@mail.tsinghua.edu.cn shji@mail.tsinghua.edu.cn.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, China. RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan. xc@mail.tsinghua.edu.cn shji@mail.tsinghua.edu.cn.
authors.forename: Shuai-Hua
authors.initials: SH
authors.lastname: Ji