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arXiv · 2112.04664

Evolution between two orbital-selective Mott phases driven by interorbital hopping

Yu Ni·Jian Sun·Ya-Min Quan·Yun Song
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Abstract

The effect of interorbital hopping on the orbital selective Mottness in a two-band correlation system is investigated by using the dynamical mean-field theory with the Lanczos method as impurity solver. We construct the phase diagram of the two-orbital Hubbard model with interorbital hopping ($t_{12})$, where the orbital selective Mott phases (OSMP) show different evolution trends. We find that the negative interorbital hopping ($t_{12}<0$) can enhance the OSMP regime upon tuning the effective bandwidth ratio. On the contrary, for the cases with positive interorbital hopping ($t_{12}>0$), the OSMP region becomes narrow with the increase of orbital hybridization until it disappears. It is also shown that a new OSMP emerges for a large enough positive interorbital hopping, owing to the role exchange of wide and narrow effective orbitals caused by the large $t_{12}$. Our results are also applicable to the hole-overdoped Ba$_2$CuO$_{4-\delta}$ superconductor, which is an orbital-selective Mott compound at half-filling.

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Yu Ni, Jian Sun, Ya-Min Quan, Yun Song. 2021-12-09. Evolution between two orbital-selective Mott phases driven by interorbital hopping. https://arxiv.org/abs/2112.04664

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