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arXiv · 2104.03644

Ultrafast metal-to-insulator switching in a strongly correlated system

Francesco Grandi·Martin Eckstein
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Abstract

Light-manipulation of correlated electronic phases in solids offers the tantalizing prospect of realizing electronic devices operating at the ultrafast time-scale. In this context, the experimental realization of non-equilibrium transitions from a metal to a band or Mott insulator has shown to be particularly elusive. Using dynamical mean-field theory, we study a simple model representing the main physical properties of the oxygen-enriched compound LaTiO$_{3+x}$. By properly optimizing the photo-doping of electrons from a low-energy band into the valence states of the system, we show it is possible to induce a valence transition from a correlated metallic state to a Mott insulator at ultrashort time scales and to contain the heating during this process, with the final non-thermal valence insulator having almost the same effective temperature of the starting metal.

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Francesco Grandi, Martin Eckstein. 2021-04-08. Ultrafast metal-to-insulator switching in a strongly correlated system. https://arxiv.org/abs/2104.03644

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