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Andreev scattering in the asymmetric ladder with preformed bosonic pairs

Karyn Le Hur
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Abstract

We discuss the phase coherence which emanates from the ladder-like proximity effect between a ``weak superconductor'' with preformed bosonic pairs (here, a single-chain Luther-Emery liquid with superconducting correlations that decay approximately as $x^{-1}$) and a Fermi gas with unpaired fermions. Carefully studying tunneling mechanism(s), we show that the boson-mediated Cooper pairing between remaining unpaired electrons results in a quasi long-range superconductivity: Superconducting correlations decay very slowly as $x^{-η}$ with $η\approx 1/2$. This process is reminiscent of the coupling of fermions to preformed bosonic pairs introduced in the context of high-Tc cuprates.

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Karyn Le Hur. 2001-06-06. Andreev scattering in the asymmetric ladder with preformed bosonic pairs. https://doi.org/10.1103/physrevb.64.060502

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