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Title: Assisted extraction of the energy level spacings and lever arms in direct current bias measurements of one-dimensional quantum wires, using an image recognition routine

A multiplexer technique is used to individually measure an array of 256 split gates on a single GaAs/AlGaAs heterostructure. This results in the generation of large volumes of data, which requires the development of automated data analysis routines. An algorithm is developed to find the spacing between discrete energy levels, which form due to transverse confinement from the split gate. The lever arm, which relates split gate voltage to energy, is also found from the measured data. This reduces the time spent on the analysis. Comparison with estimates obtained visually shows that the algorithm returns reliable results for subband spacing of split gates measured at 1.4‚ÄČK. The routine is also used to assess direct current bias spectroscopy measurements at lower temperatures (50 mK). This technique is versatile and can be extended to other types of measurements. For example, it is used to extract the magnetic field at which Zeeman-split 1D subbands cross one another.
Authors:
; ; ; ; ; ;  [1] ; ;  [1] ;  [2] ;  [3]
  1. Cavendish Laboratory, Department of Physics, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom)
  2. (United Kingdom)
  3. National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW (United Kingdom)
Publication Date:
OSTI Identifier:
22399240
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; 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; 77 NANOSCIENCE AND NANOTECHNOLOGY; ALGORITHMS; ALUMINIUM ARSENIDES; COMPARATIVE EVALUATIONS; DATA ANALYSIS; DIRECT CURRENT; ELECTRIC POTENTIAL; ENERGY LEVELS; GALLIUM ARSENIDES; HETEROJUNCTIONS; MAGNETIC FIELDS; MULTIPLEXERS; ONE-DIMENSIONAL CALCULATIONS; QUANTUM WIRES; ZEEMAN EFFECT