Doping-driven orbital-selective Mott transition in multi-band Hubbard models with crystal field splitting

TL;DR

This paper investigates how doping influences the orbital-selective Mott transition in multi-band Hubbard models with crystal field splitting, revealing doping as a key stabilizer of the orbital-selective phase.

Contribution

It introduces a phase diagram analysis of doping effects on orbital-selective Mott transitions using dynamical mean-field theory and quantum Monte Carlo methods.

Findings

Large orbital-selective Mott phase region driven by doping

Doping stabilizes the orbital-selective Mott phase

Model explains orbital-selective transitions in doped materials

Abstract

We have studied the doping-driven orbital-selective Mott transition in multi-band Hubbard models with equal band width in the presence of crystal field splitting. Crystal field splitting lifts one of the bands while leaving the others degenerate. We use single-site dynamical mean-field theory combined with continuous time quantum Monte Carlo impurity solver to calculate a phase diagram as a function of total electron filling $N$ and crystal field splitting $\Delta$. We find a large region of orbital-selective Mott phase in the phase diagram when the doping is large enough. Further analysis indicates that the large region of orbital-selective Mott phase is driven and stabilized by doping. Such models may account for the orbital-selective Mott transition in some doped realistic strongly correlated materials.