title: Prediction of intrinsic two-dimensional ferroelectrics in In2Se3and other III2-VI3van der Waals materials.
abstract: Interest in two-dimensional (2D) van der Waals materials has grown rapidly across multiple scientific and engineering disciplines in recent years. However, ferroelectricity, the presence of a spontaneous electric polarization, which is important in many practical applications, has rarely been reported in such materials so far. Here we employ first-principles calculations to discover a branch of the 2D materials family, based on In2Se3and other III2-VI3van der Waals materials, that exhibits room-temperature ferroelectricity with reversible spontaneous electric polarization in both out-of-plane and in-plane orientations. The device potential of these 2D ferroelectric materials is further demonstrated using the examples of van der Waals heterostructures of In2Se3/graphene, exhibiting a tunable Schottky barrier, and In2Se3/WSe2, showing a significant band gap reduction in the combined system. These findings promise to substantially broaden the tunability of van der Waals heterostructures for a wide range of applications.
authors.affiliation: Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Ding
authors.affiliation: Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.|Beijing Computational Science Research Center, Beijing 100084, China.
authors.forename: Jianbao
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA.|Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Yanfei
authors.identifier: 0000-0003-2082-857X
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Di
authors.initials: D
authors.lastname: Xiao
authors.affiliation: Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Gu
authors.affiliation: International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.|Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Wenguang
authors.initials: W
authors.lastname: Zhu