Transport Through Zero — Dimensional States in a Quantum Dot

  • L. P. Kouwenhoven
  • B. J. van Wees
  • C. J. P. M. Harmans
  • J. G. Williamson
Part of the NATO ASI Series book series (NSSB, volume 214)


The importance of magnetic edge channels for transport in the quantum Hall regime is no longer a question of doubt. This simplifies considerably the basic description of the transport properties of a two dimensional electron gas (2DEG) in a high magnetic field.1 The right- and left-moving electrons, which carry the net current, are located at opposite boundaries of the sample and travel in truly one-dimensional edge channels. Under usual circumstances all occupied edge channels contribute equally to the conductance, which results in the quantization of the Hall resistance. However, it was recently shown that edge channels can be selectively populated or detected, when quantum point contacts (QPC’s) are used as current or voltage probes respectively.2,3 An anomalous integer quantum Hall effect was observed, determined by the number of transmitted edge channels through the QPC probes, instead of the number of occupied edge channels in the bulk 2DEG. It was also concluded that the one dimensional transport through magnetic edge channels can occur adiabatically (i.e. with conservation of quantum-channel-number and velocity direction) even on macroscopic length scales much larger than the (zero magnetic field) transport mean free path.3,4


Gate Voltage High Magnetic Field Equipotential Line Hall Resistance Edge Channel 
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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • L. P. Kouwenhoven
    • 1
  • B. J. van Wees
    • 1
  • C. J. P. M. Harmans
    • 1
  • J. G. Williamson
    • 2
  1. 1.Faculty of Applied PhysicsDelft University of TechnologyDelftThe Netherlands
  2. 2.Philips Research LaboratoriesEindhovenThe Netherlands

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