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Activated Transport in the individual Layers that form the $ν_T$=1 Exciton Condensate

R. D. Wiersma·J. G. S. Lok·S. Kraus·W. Dietsche·K. von Klitzing·D. Schuh·M. Bichler·H. -P. Tranitz·W. Wegscheider
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Abstract

We observe the total filling factor $ν_{T}$=1 quantum Hall state in a bilayer two-dimensional electron system with virtually no tunnelling. We find thermally activated transport in the balanced system with a monotonic increase of the activation energy with decreasing $d/\ell_B$ below 1.65. In the imbalanced system we find activated transport in each of the layers separately, yet the activation energies show a striking asymmetry around the balance point. This implies that the gap to charge-excitations in the {\em individual} layers is substantially different for positive and negative imbalance.

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R. D. Wiersma, J. G. S. Lok, S. Kraus, W. Dietsche, K. von Klitzing, D. Schuh, M. Bichler, H. -P. Tranitz, W. Wegscheider. 2004-07-22. Activated Transport in the individual Layers that form the $ν_T$=1 Exciton Condensate. https://doi.org/10.1103/physrevlett.93.266805

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