Dynamics of photo-induced metallic states in correlated materials
21.11.2014 at 09:00
Using ultrafast lasers one can probe condensed matter systems on the intrinsic timescale of their microscopic constituents. Observations like photo-induced metal-insulator transitions or photo-induced superconductivity suggest ways to control complex phases and phase transitions within femtoseconds. Often, however, even a qualitative understanding of the underlying physical processes is missing. In this talk I briefly discuss the recent development of theoretical approaches to quantum many-body systems out of equilibrium based on dynamical mean-field theory (DMFT) and its generalizations [Aoki et al, Rev. Mod. Phys. 86, 779 (2014)].
I will then focus on results concerning the dynamics of photo-induced metallic states: In a Mott insulator, antiferromagnetic fluctuations are of particular importance in this respect, and govern both the relaxation of photo-induced states and non-linear transport [Eckstein and Werner, PRL 113, 076405 (2014)]. Another interesting case are photo-induced states in materials with
strong electron-phonon coupling. Using an exact solution of the single-electron Holstein model in nonequilibrium DMFT we analyze characteristic features of excited polaron states and metastable delocalized states in a transient photo-induced metal.
A 450 - Theresienstr. 37