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Correlated quantum percolation in the lowest Landau level

Nancy Sandler·Hamid Maei·Jane' Kondev
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Abstract

Our understanding of localization in the integer quantum Hall effect is informed by a combination of semi-classical models and percolation theory. Motivated by the effect of correlations on classical percolation we study numerically electron localization in the lowest Landau level in the presence of a power-law correlated disorder potential. Careful comparisons between classical and quantum dynamics suggest that the extended Harris criterion is applicable in the quantum case. This leads to a prediction of new localization quantum critical points in integer quantum Hall systems with power-law correlated disorder potentials. We demonstrate the stability of these critical points to addition of competing short-range disorder potentials, and discuss possible experimental realizations.

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Nancy Sandler, Hamid Maei, Jane' Kondev. 2003-11-20. Correlated quantum percolation in the lowest Landau level. https://doi.org/10.1103/physrevb.70.045309

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