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arXiv · 1908.08693

$η$--paired superconducting hidden phase in photodoped Mott insulators

Jiajun Li·Denis Golez·Philipp Werner·Martin Eckstein
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Abstract

We show that a metastable $η$--pairing superconducting phase can be induced by photodoping doublons and holes into a strongly repulsive fermionic Hubbard model. The doublon-hole condensate originates from an intrinsic doublon-hole exchange interaction and does not rely on the symmetry of the half-filled Hubbard model. It extends over a wide range of doublon densities and effective temperatures. Different non-equilibrium protocols to realize this state are proposed and numerically tested. We also study the optical conductivity in the superconducting phase, which exhibits ideal metallic behavior, i.e., a delta function at zero-frequency in the conductivity, in conjunction with a negative conductivity at large frequencies. These characteristic optical properties can provide a fingerprint of the $η$-pairing phase in pump-probe experiments.

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Jiajun Li, Denis Golez, Philipp Werner, Martin Eckstein. 2020-10-06. $η$--paired superconducting hidden phase in photodoped Mott insulators. https://doi.org/10.1103/physrevb.102.165136

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