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arXiv · 1204.1847

Photoinduced magnetic bound state in itinerant correlated electron system with spin-state degree of freedom

Yu Kanamori·Jun Ohara·Sumio Ishihara
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Abstract

Photo-excited state in correlated electron system with spin-state degree of freedom is studied. We start from the two-orbital extended Hubbard model where energy difference between the two orbitals is introduced. Photo-excited metastable state is examined based on the effective model Hamiltonian derived by the two-orbital Hubbard model. Spin-state change is induced by photo-irradiation in the low-spin band insulator near the phase boundary. High-spin state is stabilized by creating a ferromagnetic bound state with photo-doped hole carriers. An optical absorption occurs between the bonding and antibonding orbitals inside of the bound state. Time-evolution for photo-excited states is simulated in the time-dependent mean-field scheme. Pair-annihilations of the photo-doped electron and hole generate the high-spin state in a low-spin band insulator. We propose that this process is directly observed by the time-resolved photoemission experiments.

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Yu Kanamori, Jun Ohara, Sumio Ishihara. 2012-04-09. Photoinduced magnetic bound state in itinerant correlated electron system with spin-state degree of freedom. https://doi.org/10.1103/physrevb.86.045137

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