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Direct observation of the charging of a 2D electron gas through an incompressible strip in the quantum Hall regime

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 Added by Gleb Finkelstein
 Publication date 2001
  fields Physics
and research's language is English




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Using charge accumulation imaging, we measure the charge flow across an incompressible strip and follow its evolution with magnetic field. The strip runs parallel to the edge of a gate deposited on the sample and forms at positions where an exact number of integer Landau levels is filled. An RC model of charging fits the data well and enables us to determine the longitudinal resistance of the strip. Surprisingly, we find that the strip becomes more resistive as its width decreases.

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