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arXiv · 2510.27483

Photoinduced excitonic magnetism in a multiorbital Hubbard system

Lei Geng·Sujay Ray·Philipp Werner
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Abstract

Multiorbital Hubbard models with Hund coupling and crystal-field splitting exhibit an instability toward spin-triplet excitonic order in the parameter regime characterized by strong local spin fluctuations. Upon chemical doping, two distinct types of excitonic ferromagnetism have been reported. Using steady-state nonequilibrium dynamical mean-field theory, we demonstrate that photo-doped half-filled systems can host nonthermal counterparts of these excitonic phases and exhibit a rich phase diagram in the space of photo-doping and crystal field splitting. Photo-doping a spin-triplet excitonic insulator provides a route towards nonequilibrium control of magnetic order.

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Lei Geng, Sujay Ray, Philipp Werner. 2025-10-31. Photoinduced excitonic magnetism in a multiorbital Hubbard system. https://doi.org/10.1103/x12m-1s8v

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