We reformulate the time-dependent Gutzwiller approximation by M. Schir\'o and M. Fabrizio [Phys. Rev. Lett. 105, 076401 (2010)] in the framework of slave-boson mean-field theory, which is used to investigate the dynamical Mott transition of the generic two-band Hubbard model at half filling upon an interaction quench. Interorbital fluctuations lead to notable changes with respect to the single-band case. The singular dynamical transition is replaced by a broad regime of long-lived fluctuations between metallic and insulating states, accompanied by intriguing precursor behavior. A mapping to a spin model proves helpful to analyze the different regions in terms of the evolution of an Ising-like order parameter. Contrary to the static case, singlet occupations remain vital in the Mott-insulating regime with finite Hund's exchange.
|Titolo:||Extended dynamic Mott transition in the two-band Hubbard model out of equilibrium|
|Autori:||Behrmann, M.; Fabrizio, M.; Lechermann, F.|
|Rivista:||PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS|
|Data di pubblicazione:||2013|
|Digital Object Identifier (DOI):||10.1103/PhysRevB.88.035116|
|Appare nelle tipologie:||1.1 Journal article|