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arXiv · 1512.00275

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

Yilin Wang·Li Huang·Liang Du·Xi Dai
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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 $Δ$. 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.

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Yilin Wang, Li Huang, Liang Du, Xi Dai. 2016-01-11. Doping-driven orbital-selective Mott transition in multi-band Hubbard models with crystal field splitting. https://arxiv.org/abs/1512.00275

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