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Prospecting for the superfluid transition in electron-hole coupled quantum wells using Coulomb drag

Ben Yu-Kuang Hu
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Abstract

I investigate the possibility of using Coulomb drag to detect a precursor of the predicted (but as yet not definitively observed) superfluid transition in electron-hole coupled quantum wells. The drag transresisitivity $ρ_{21}$ is shown to be significantly enhanced above the transition temperature $T_c$ and to diverge logarithmically as $T\to T_c^+$, due to electron-hole pairing fluctuations which are somewhat analogous to the Maki-Thompson contribution to conductivity in metals above the superconducting $T_c$. The enhancement in $ρ_{21}$ is estimated to be detectable at temperatures much higher than $T_c$.

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Ben Yu-Kuang Hu. 1999-08-10. Prospecting for the superfluid transition in electron-hole coupled quantum wells using Coulomb drag. https://arxiv.org/abs/cond-mat/9908137

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