'Fully automated system for the characterization of standard reference resistors using the quantum hall effect.'

The authors have constructed a self-contained, fully automatic system for the characterization of laboratory transfer resistance standards. A novel feature is the integration of all elements into a single cryogenic system. The instrument allows direct comparison of standard resistors with the Quantum Hall resistance in GaAs/GaAlAs heterostructures. At low temperature the Hall voltage exhibits plateaus of constant value as the external magnetic field is increased, corresponding to a Quantum Hall Resistance equal to h/e²n, where h is Planck's constant, e the electron charge and n an integer. The resistance of the transfer standard can therefore be determined from fundamental physical constants.