Conductance fluctuations and chaotic scattering in ballistic microstructures

C. M. Marcus; A. J. Rimberg; R. M. Westervelt; P. F. Hopkins; A. C. Gossard

doi:10.1103/PhysRevLett.69.506

Conductance fluctuations and chaotic scattering in ballistic microstructures

C. M. Marcus, A. J. Rimberg, R. M. Westervelt, P. F. Hopkins, and A. C. Gossard

Phys. Rev. Lett. 69, 506 – Published 20 July 1992

Abstract

We report detailed measurements of the low-temperature magnetoconductance in ballistic microstructures in the shape of a ‘‘chaotic’’ stadium and a circle with quantum-point-contact leads. Both structures show large, aperiodic, conductance fluctuations as a function of perpendicular magnetic field, and a zero-field resistance peak indicating geometry-dependent enhanced backscattering. Power spectra of fluctuations are consistent with recent semiclassical analyses based on quantum chaotic scattering, with the circle showing enhanced high-frequency spectral content.

Received 9 January 1992

DOI:https://doi.org/10.1103/PhysRevLett.69.506

Authors & Affiliations

C. M. Marcus, A. J. Rimberg, R. M. Westervelt, P. F. Hopkins, and A. C. Gossard

Division of Applied Sciences and Department of Physics, Harvard University, Cambridge, Massachusetts 02138
Materials Department, University of California–Santa Barbara, Santa Barbara, California 93106