Four-terminal magnetoresistance of a two-dimensional electron-gas constriction in the ballistic regime

H. van Houten; C. W. J. Beenakker; P. H. M. van Loosdrecht; T. J. Thornton; H. Ahmed; M. Pepper; C. T. Foxon; J. J. Harris

doi:10.1103/PhysRevB.37.8534

Rapid Communication

Four-terminal magnetoresistance of a two-dimensional electron-gas constriction in the ballistic regime

H. van Houten, C. W. J. Beenakker, P. H. M. van Loosdrecht, T. J. Thornton, H. Ahmed, M. Pepper, C. T. Foxon, and J. J. Harris

Phys. Rev. B 37, 8534(R) – Published 15 May 1988

Abstract

A novel negative magnetoresistance effect is found in four-terminal measurements of the voltage drop across a short constriction of variable width in a high-mobility two-dimensional electron gas. The effect is interpreted as the suppression by a magnetic field of the geometrical constriction resistance in the ballistic regime. Quantitative agreement with a simple model based on a Landauer-type formula is obtained.