Mott transition studied by cellular dynamical mean field theory
POSTER
Abstract
We study metal-insulator transitions between Mott insulators and metals. The transition mechanism completely different from the original dynamical mean field theory (DMFT) emerges from a cluster extension of it. A consistent picture suggests that the quasiparticle weight $Z$ remains nonzero through metals and suddenly jumps to zero at the transition, while the gap opens continuously in the insulators. This is in contrast with the original DMFT, where $Z$ continuously vanishes but the gap opens discontinuously. The present results arising from electron differentiation in momentum space agree with recent puzzling bulk-sensitive experiments on CaVO$_3 $ and SrVO$_3$. Details of the mechanism of Mott transition is studied through doublon-doublon, doublon-holon and spin-spin dynamical susceptibilities.