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Title: Towards a graphene-based quantum impedance standard

Precision measurements of the quantum Hall resistance with alternating current (ac) in the kHz range were performed on epitaxial graphene in order to assess its suitability as a quantum standard of impedance. The quantum Hall plateaus measured with alternating current were found to be flat within one part in 10{sup 7}. This is much better than for plain GaAs quantum Hall devices and shows that the magnetic-flux-dependent capacitive ac losses of the graphene device are less critical. The observed frequency dependence of about −8 × 10{sup −8}/kHz is comparable in absolute value to the positive frequency dependence of plain GaAs devices, but the negative sign is attributed to stray capacitances which we believe can be minimized by a careful design of the graphene device. Further improvements thus may lead to a simpler and more user-friendly quantum standard for both resistance and impedance.
Authors:
; ; ;  [1] ; ;  [2] ;  [3]
  1. Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany)
  2. Department of Micro- and Nanosciences, Aalto University, Micronova, Tietotie 3, 02150 Espoo (Finland)
  3. MIKES, Tekniikantie 1, P.O. Box, 02151 Espoo (Finland)
Publication Date:
OSTI Identifier:
22310923
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AC LOSSES; ACCURACY; ALTERNATING CURRENT; CAPACITANCE; ELECTRIC CONDUCTIVITY; EPITAXY; FREQUENCY DEPENDENCE; GALLIUM ARSENIDES; GRAPHENE; IMPEDANCE; MAGNETIC FLUX; MAGNETIC PROPERTIES