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arXiv · 2403.07737

Photo-induced Ferromagnetic and Superconducting Orders in Multi-orbital Hubbard Models

Sujay Ray·Philipp Werner
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Abstract

The search for hidden orders in photoexcited lattice systems is an active research field driven by experimental reports of light-induced or light-stabilized phases. In this study, we investigate hidden electronic orders in strongly correlated two-orbital Hubbard models with orbital-dependent bandwidths. In equilibrium, the half-filled systems are antiferromagnetically ordered. Using non-equilibrium dynamical mean field theory we demonstrate the appearance of nonthermal ferromagnetic order in the photo-doped state, if the two bandwidths are sufficiently different, and its coexistence with spin-singlet $\eta$-superconductivity in the high photo-doping region. Spin-triplet $\eta$-superconducting order appears instead if the two bandwidths are comparable. The rich nonequilibrium phasediagram uncovered in this work shows that Mott insulating multi-orbital systems provide an interesting platform for the realization of nonthermal electronic orders.

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Sujay Ray, Philipp Werner. 2024-03-12. Photo-induced Ferromagnetic and Superconducting Orders in Multi-orbital Hubbard Models. https://doi.org/10.1103/physrevb.110.l041109

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