# Ultrafast doublon dynamics in photoexcited $1T$-${\mathrm{TaS}}_{2}$

• Ligges, M. Faculty of Physics, University of Duisburg-Essen, Germany
• Avigo, I. Faculty of Physics, University of Duisburg-Essen, Germany
• Golež, Denis Department of Physics, University of Fribourg, Switzerland
18.04.2018
Published in:
• Physical Review Letters. - 2018, vol. 120, no. 16, p. 166401
English Strongly correlated materials exhibit intriguing properties caused by intertwined microscopic interactions that are hard to disentangle in equilibrium. Employing nonequilibrium time-resolved photoemission spectroscopy on the quasi-two- dimensional transition-metal dichalcogenide 1T-TaS2, we identify a spectroscopic signature of doubly occupied sites (doublons) that reflects fundamental Mott physics. Doublon-hole recombination is estimated to occur on timescales of electronic hopping ℏ/J≈14 fs. Despite strong electron-phonon coupling, the dynamics can be explained by purely electronic effects captured by the single-band Hubbard model under the assumption of weak hole doping, in agreement with our static sample characterization. This sensitive interplay of static doping and vicinity to the metal- insulator transition suggests a way to modify doublon relaxation on the few- femtosecond timescale.
Faculty
Faculté des sciences et de médecine
Department
Département de Physique
Language
• English
Classification
Physics