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DC four point resistance of a double barrier quantum pump

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 Added by Federico Foieri
 Publication date 2008
  fields Physics
and research's language is English




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We investigate the behavior of the dc voltage drop in a periodically driven double barrier structure (DBS) sensed by voltages probes that are weakly coupled to the system. We find that the four terminal resistance $R_{4t}$ measured with the probes located outside the DBS results identical to the resistance measured in the same structure under a stationary bias voltage difference between left and right reservoirs. This result, valid beyond the adiabatic pumping regime, can be taken as an indication of the universal character of $R_{4t}$ as a measure of the resistive properties of a sample, irrespectively of the mechanism used to induce the transport.



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