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arXiv · 1903.08262

Precursors to Exciton Condensation in Quantum Hall Bilayers

J. P. Eisenstein·L. N. Pfeiffer·K. W. West
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Abstract

Tunneling spectroscopy reveals evidence for interlayer electron-hole correlations in quantum Hall bilayer two-dimensional electron systems at layer separations near, but above, the transition to the incompressible exciton condensate at total Landau level filling $ν_T=1$. These correlations are manifested by a non-linear suppression of the Coulomb pseudogap which inhibits low energy interlayer tunneling in weakly-coupled bilayers. The pseudogap suppression is strongest at $ν_T=1$ and grows rapidly as the critical layer separation for exciton condensation is approached from above.

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J. P. Eisenstein, L. N. Pfeiffer, K. W. West. 2019-08-08. Precursors to Exciton Condensation in Quantum Hall Bilayers. https://doi.org/10.1103/physrevlett.123.066802

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