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arXiv · 1112.4674

Diamagnetism and flux creep in bilayer exciton superfluids

P. R. Eastham·N. R. Cooper·D. K. K. Lee
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Abstract

We discuss the diamagnetism induced in an isolated quantum Hall bilayer with total filling factor one by an in-plane magnetic field. This is a signature of counterflow superfluidity in these systems. We calculate magnetically induced currents in the presence of pinned vortices nucleated by charge disorder, and predict a history-dependent diamagnetism that could persist on laboratory timescales. For current samples we find that the maximum in-plane moment is small, but with stronger tunneling the moments would be measurable using torque magnetometry. Such experiments would allow the persistent currents of a counterflow superfluid to be observed in an electrically isolated bilayer.

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P. R. Eastham, N. R. Cooper, D. K. K. Lee. 2011-12-20. Diamagnetism and flux creep in bilayer exciton superfluids. https://doi.org/10.1103/physrevb.85.165320

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