Local Analysis of Disorder Driven Insulator-to-Metal Transition in the 2D Mott-Hubbard Model.

We show that increasing the number of disordered sites drives an insulator-to-metal transition in 2D Mott-Hubbard insulator. In our numerical approach we treat the spatial disorder exactly and use real-space Hartree-Fock mean-field decomposition for electron-electron interactions. These numerical methods provide insight into the localization physics as it relates to the interplay between disorder and interactions. Our results reveal an asymmetric closing of the Mott-gap and formation of a pseudogap in the density of states arising from inhomogeneous disorder potential mediated screening of the Hubbard interaction. Global lattice transport properties exhibit a transition from an insulating, gapped optical conductivity to an ungapped, metallic phase. A local picture consisting of magnetic order, compressibility, and charge mobility evolves toward a paramagnetic, metallic state with increasing disorder number due to correlations with regions of greater effective disorder. We present these local measurements to explain and provide avenues to characterize disorder induced transitions in ongoing experimental efforts.