Electronic structures and unusually robust bandgap in an ultrahigh-mobility layered oxide semiconductor, Bi2O2Se

DOI: 10.1126/sciadv.aat8355

Authors: Cheng Chen (University of Oxford) , Meixiao Wang (ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center) , Jinxiong Wu (Peking University) , Huixia Fu (Weizmann Institute of Science) , Haifeng Yang (University of Oxford) , Zhen Tian (ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center) , Teng Tu (Peking University) , Han Peng (University of Oxford) , Yan Sun (Max Planck Institute for Chemical Physics of Solids) , Xiang Xu (Tsinghua University; Advanced Light Source) , Juan Jiang (ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center; Advanced Light Source; Pohang University of Science and Technology) , Niels B. M. Schroeter (University of Oxford; Paul Scherrer Institute) , Yiwei Li (University of Oxford) , Ding Pei (University of Oxford) , Shuai Liu (ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center) , Sandy A. Ekahana (University of Oxford) , Hongtao Yuan (Nanjing University) , Jiamin Xue (ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center) , Gang Li (ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center) , Jinfeng Jia (Shanghai Jiao Tong University) , Zhongkai Liu (Shanghai Jiao Tong University) , Binghai Yan (Weizmann Institute of Science) , Hailin Peng (Peking University) , Yulin Chen (University of Oxford; ShanghaiTech University; Chinese Academy of Sciences–Shanghai Science Research Center; Tsinghua University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Science Advances , VOL 4

State: Published (Approved)
Published: September 2018
Diamond Proposal Number(s): 18005

Abstract: Semiconductors are essential materials that affect our everyday life in the modern world. Two-dimensional semiconductors with high mobility and moderate bandgap are particularly attractive today because of their potential application in fast, low-power, and ultrasmall/thin electronic devices. We investigate the electronic structures of a new layered air-stable oxide semiconductor, Bi2O2Se, with ultrahigh mobility (~2.8 × 105 cm2/V⋅s at 2.0 K) and moderate bandgap (~0.8 eV). Combining angle-resolved photoemission spectroscopy and scanning tunneling microscopy, we mapped out the complete band structures of Bi2O2Se with key parameters (for example, effective mass, Fermi velocity, and bandgap). The unusual spatial uniformity of the bandgap without undesired in-gap states on the sample surface with up to ~50% defects makes Bi2O2Se an ideal semiconductor for future electronic applications. In addition, the structural compatibility between Bi2O2Se and interesting perovskite oxides (for example, cuprate high–transition temperature superconductors and commonly used substrate material SrTiO3) further makes heterostructures between Bi2O2Se and these oxides possible platforms for realizing novel physical phenomena, such as topological superconductivity, Josephson junction field-effect transistor, new superconducting optoelectronics, and novel lasers.

Diamond Keywords: Semiconductors

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Added On: 18/10/2018 11:07

Documents:
eaat8355.full.pdf

Discipline Tags:

Quantum Materials Hard condensed matter - electronic properties Physics Hard condensed matter - structures Electronics Materials Science Thermoelectrics

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)