title: Conductance fluctuations and quantum chaotic scattering in semiconductor microstructures.
abstract: We review recent experiments on aperiodic conductance fluctuations in ballistic GaAs/AlGaAs microstructures in the shape of a stadium billiard and a circle with point-contact leads, measured at millikelvin temperatures. Much of the observed behavior can be analyzed within a semiclassical approach to quantum chaotic scattering. After a brief review of the Landauer-Buttiker formulation of coherent transport, a variety of novel experimental phenomena and comparisons to semiclassical theory are presented. In particular, we discuss quantum-enhanced backscattering, the power spectrum of conductance fluctuations, crossover to the high-magnetic-field and tunneling regimes, and an application allowing the rate of phase-randomizing scattering to be measured in chaotic ballistic microstructures.
authors.affiliation: Division of Applied Sciences and Department of Physics, Harvard University, Cambridge, Massachusetts 02138Department of Materials, University of California, Santa Barbara, California 93106.
authors.forename: C. M.
authors.initials: CM
authors.lastname: Marcus
authors.forename: R. M.
authors.initials: RM
authors.lastname: Westervelt
authors.forename: P. F.
authors.initials: PF
authors.lastname: Hopkins
authors.forename: A. C.
authors.initials: AC
authors.lastname: Gossard