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arXiv:2305.06760 · Physical review. B./Physical review. B

Nonthermal superconductivity in photodoped multiorbital Hubbard systems

Sujay Ray, Yuta Murakami, Philipp Werner

Published Nov 27, 2023• 13 citations
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Abstract

Superconductivity in laser-excited correlated electron systems has attracted considerable interest due to reports of light-induced superconductinglike states. Here we explore the possibility of nonthermal superconducting order in strongly interacting multiorbital Hubbard systems, using nonequilibrium dynamical mean field theory. We find that a staggered $\ensuremath{\eta}$-type superconducting phase can be realized on a bipartite lattice in the high photodoping regime, if the effective temperature of the photocarriers is sufficiently low. The $\ensuremath{\eta}$ superconducting state is stabilized by Hund coupling---a positive Hund coupling favors orbital-singlet spin-triplet $\ensuremath{\eta}$ pairing, whereas a negative Hund coupling stabilizes spin-singlet orbital-triplet $\ensuremath{\eta}$ pairing.

DOI
10.1103/physrevb.108.174515

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High-temperature ηηη-pairing superconductivity in the photodoped Hubbard model
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