skip to main content

SciTech ConnectSciTech Connect

Title: Gate-tunable coherent transport in Se-capped Bi{sub 2}Se{sub 3} grown on amorphous SiO{sub 2}/Si

A topological insulator (TI) is an exotic material that has a bulk insulating gap and metallic surface states with unique spin-momentum locking characteristics. Despite its various important applications, large scale integration of TI into MOSFET technologies and its coherent transport study are still rarely explored. Here, we report the growth of high quality Bi{sub 2}Se{sub 3} thin film on amorphous SiO{sub 2}/Si substrate using MBE. By controlling the thickness of the film at ∼7 nm and capping the as grown film in situ with a 2 nm-thick Se layer, largest electrostatic field effect is obtained and the resistance is changed by almost 300%. More importantly, pronounced gate-tunable weak antilocalization (WAL) is observed, which refers to modulation of α from ∼−0.55 to ∼−0.2 by applying a back gate voltage. The analysis herein suggests that the significant gate-tunable WAL is attributable to the transition from weak disorder into intermediate disorder regime when the Fermi level is shifted downward by increasing the negative back gate voltage. Our findings may pave the ways towards the development of TI-based MOSFET and are promising for the applications of electric-field controlled spintronic and magnetic device.
Authors:
; ;  [1] ; ;  [2] ;  [1] ;  [3] ;  [4] ; ;  [5] ;  [6]
  1. Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China)
  2. Department of Physics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China)
  3. (AOTC), National Cheng Kung University, Tainan 70101, Taiwan (China)
  4. (TCECM), Ministry of Science and Technology, Taipei 10622, Taiwan (China)
  5. School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei, Anhui 230009 (China)
  6. M.N. Miheev Institute of Metal Physics, Ekaterinburg 620137 (Russian Federation)
Publication Date:
OSTI Identifier:
22483148
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BISMUTH SELENIDES; ELECTRIC FIELDS; ELECTRIC POTENTIAL; EQUIPMENT; FERMI LEVEL; MODULATION; MOSFET; SILICON OXIDES; SUBSTRATES; SURFACES; THICKNESS; THIN FILMS; TOPOLOGY