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Dissipationless transport in low density bilayer systems

Ady Stern·S. Das Sarma·Matthew P. A. Fisher·S. M. Girvin
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Abstract

In a bilayer electronic system the layer index may be viewed as the z-component of an isospin-1/2. An XY isospin-ordered ferromagnetic phase was observed in quantum Hall systems and is predicted to exist at zero magnetic field at low density. This phase is a superfluid for opposite currents in the two layers. At B=0 the system is gapless but superfluidity is not destroyed by weak disorder. In the quantum Hall case, weak disorder generates a random gauge field which probably does not destroy superfluidity. Experimental signatures include Coulomb drag and collective mode measurements.

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Ady Stern, S. Das Sarma, Matthew P. A. Fisher, S. M. Girvin. 1999-08-17. Dissipationless transport in low density bilayer systems. https://doi.org/10.1103/physrevlett.84.139

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