Abstract
The Hall conductivity σxy of a two-dimensional electron system is quantized in units of e2 h when the Fermi level is located in the gap between two Landau levels. We consider the deviation of σxy from a quantized value caused by the thermal activation of electrons to the extended states for the case of a long range random potential. This deviation is of the form σxy*exp( -Δ T). The prefactor σxy* is equal to e2 h at temperatures above a characteristic value T2. Below T2, σxy* decays according to a power law: σxy* = e2 h( T T2)γ. The generalization to fractional Hall plateaux is discussed.
Original language | English (US) |
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Pages (from-to) | 503-507 |
Number of pages | 5 |
Journal | Solid State Communications |
Volume | 94 |
Issue number | 7 |
DOIs | |
State | Published - May 1995 |
Bibliographical note
Funding Information:Useful discussionsw ith I. M. Ruzin and D. G. Polya-kov are greatly appreciated.T hii work wss supported by NSF under Grant No. DMR-9321417.
Keywords
- A. semiconductors D. quantum Hall effect