Photoinduced insulator-metal transition in paramagnetic (V1-xCrx)2O3 1- x Cr x ) 2 O 3

Pump-probe experiments with femtosecond time resolution can be used to disentangle the electronic dynamics from the lattice response and thus provide valuable insights into the nonequilibrium behavior of correlated materials. In Cr-doped V2O3, a multiorbital Mott-Hubbard material which has been intensively investigated for decades, time-resolved experiments reported a photoinduced insulator-metal transition leading to a transient metal state with nonthermal properties. Here, we combine nonequilibrium dynamical mean-field theory with realistic first-principles modeling to simulate the ultrafast response of this material to a laser excitation. Our calculations reproduce the insulating initial state, with orbital occupations in agreement with experiment, and reveal an ultrafast pump-induced gap filling associated with a charge reshuffling between the e pi g and a1g orbitals. However, in contrast to the related compound VO2, the electronic system thermalizes within a few tens of femtoseconds and we find no evidence for the existence of a metastable nonthermal metal. This suggests that the reported nonthermal behavior in the experiments may be associated with the mismatch between the electronic and lattice temperatures.