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Selective Population of Modes in Electron Waveguides: Bend Resistances and Quenching of the Hall Resistance

  • Harold U. Baranger
  • A. Douglas Stone
Part of the NATO ASI Series book series (NSSB, volume 214)

Abstract

In determining the salient characteristics of transport in small structures, the size of the sample compared to the important length scales in the material— the fermi wavelength, the elastic mean-free-path, the phase coherence length, and the localization length— defines several different regimes. In the last five years a great deal of attention has been devoted to studying the conductance fluctuations present in the coherent diffusive regime for which the system size is of the order of the phase-breaking length and much larger than the elastic scattering length.[1] More recent work has established that in certain materials electrons can travel without significant scattering or dephasing over a surprisingly large distance. The material of choice in this regard is the two-dimensional electron gas which is created at the GaAs/GaAlAs interface in modulation-doped heterostructures for which the elastic mean-free-path can be greater than 1 μm and the phase-breaking length can be greater than 10 μm. Furthermore, one can define wires in this material with a width of order the fermi wavelength.[2] Studies of transport in these “quasi-onedimensional ballistic microstructures” have revealed many novel features.

Keywords

Fermi Energy Selective Population Hall Resistance Cross Structure Forward Transmission 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • Harold U. Baranger
    • 1
  • A. Douglas Stone
    • 2
  1. 1.AT&T Bell Laboratories 4G-314HolmdelUSA
  2. 2.Applied PhysicsYale UniversityNew HavenUSA

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