Photo-induced nonthermal metals

P. Werner,1 J. Chen,1 F. Petocchi,2 M. Eckstein3

1Department of Physics, University of Fribourg, 1700 Fribourg, Switzerland

2Department of Quantum Matter Physics, University of Geneva, 1211 Geneva, Switzerland

3Institute of Theoretical Physics, University of Hamburg, 20355 Hamburg, Germany

Several insulating materials can be switched by laser pulses into transient metal states with apparently nonthermal properties [1-4]. Often, this has been interpreted as a nonthermal closing of a Mott gap. An alternative mechanism is the generation of in-gap states by the nonthermal population of multiplets (e. g. singlet-triplet excitations in dimerized systems), or the nonthermal reshuffling of charge between orbitals. I will present recent nonequilibrium dynamical mean field theory studies of model systems, which provide insights into the nature of photo-induced nonthermal metal states in 1T-TaS2 [5] and rare earth nickelates [6], and realistic simulations of the photo-induced dynamics in VO2 [7], which clarify the excitation and charge reshuffling processes leading to the nonthermal monoclinic metal phase.

1. M. Ligges et al. Phys. Rev. Lett. 120, 166401 (2018)
2. J. Dong et al., arxiv:2210.11052 (2022)
3. V. R. Morrison et al., Science 346, 445 (2014)
4. D. Wegkamp et al., Phys. Rev. Lett. 113, 216401 (2014)
5. F. Petocchi et al., Phys. Rev. B 107, 165102 (2023)
6. P. Werner et al., Phys. Rev. B 107, 035157 (2023)
7. J. Chen, et al., arxiv:2310.18195 (2023)