Prediction of quantization of magnetic flux in double-layer exciton superfluids

Abstract

Currently, there is no way to detect unambiguously the possible phase coherence of an exciton condensate in an electron-hole double layer. Here, we show that, despite the fact that excitons are charge neutral, the double-layer exciton superfluid exhibits a diamagnetic response. In devices with specific circular geometry, the magnetic-flux threading between the layers must be quantized in units of heχm, where χm is the diamagnetic susceptibility of the device. We discuss possible experimental realizations of the predicted unconventional flux quantization. © 2011 American Physical Society.