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arXiv · 1512.04399

Photoinduced phase transitions in narrow-gap Mott insulators: the case of VO$_2$

Zhuoran He·Andrew J. Millis
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Abstract

We study the nonequilibrium dynamics of photoexcited electrons in the narrow-gap Mott insulator VO$_2$. The initial stages of relaxation are treated using a quantum Boltzmann equation methodology, which reveals a rapid ($\sim$ femtosecond time scale) relaxation to a pseudothermal state characterized by a few parameters that vary slowly in time. The long-time limit is then studied by a Hartree-Fock methodology, which reveals the possibility of nonequilibrium excitation to a new metastable $M_1$ metal phase that is qualitatively consistent with a recent experiment. The general physical picture of photoexcitation driving a correlated electron system to a new state that is not accessible in equilibrium may be applicable in similar materials.

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Zhuoran He, Andrew J. Millis. 2015-12-14. Photoinduced phase transitions in narrow-gap Mott insulators: the case of VO$_2$. https://doi.org/10.1103/physrevb.93.115126

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