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Title: Magneto-transport of an electron bilayer system in an undoped Si/SiGe double-quantum-well heterostructure

We report the design, the fabrication, and the magneto-transport study of an electron bilayer system embedded in an undoped Si/SiGe double-quantum-well heterostructure. Combined Hall densities (n{sub Hall}) ranging from 2.6 × 10{sup 10} cm{sup −2} to 2.7 × 10{sup 11} cm{sup −2} were achieved, yielding a maximal combined Hall mobility (μ{sub Hall}) of 7.7 × 10{sup 5} cm{sup 2}/(V ⋅ s) at the highest density. Simultaneous electron population of both quantum wells is clearly observed through a Hall mobility drop as the Hall density is increased to n{sub Hall} > 3.3 × 10{sup 10} cm{sup −2}, consistent with Schrödinger-Poisson simulations. The integer and fractional quantum Hall effects are observed in the device, and single-layer behavior is observed when both layers have comparable densities, either due to spontaneous interlayer coherence or to the symmetric-antisymmetric gap.
Authors:
; ;  [1] ; ; ;  [2] ;  [3]
  1. Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)
  2. Department of Electrical Engineering and Graduate Institute of Electronic Engineering, National Taiwan University, Taipei 10617, Taiwan (China)
  3. (China)
Publication Date:
OSTI Identifier:
22398872
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 14; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; CARRIER MOBILITY; COMPARATIVE EVALUATIONS; ELECTRONS; FABRICATION; GERMANIUM SILICIDES; HALL EFFECT; HETEROJUNCTIONS; LAYERS; MAGNETORESISTANCE; QUANTUM WELLS; SILICON; SYMMETRY