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arXiv · 1110.4045

Investigation of on-site inter-orbital single electron hoppings in general multi-orbital systems

Qingguo Feng·Peter M. Oppeneer
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Abstract

A general multi-orbital Hubbard model, which includes on-site inter-orbital electron hoppings, is introduced and studied. It is shown that the on-site inter-orbital single electron hopping is one of the most basic interactions. Two electron spin-flip and pair-hoppings are shown to be correlation effects of higher order than the on-site inter-orbital single hopping. It is shown how the double and higher hopping interactions can be well-defined for arbitrary systems. The two-orbital Hubbard model is studied numerically to demonstrate the influence of the single electron hopping effect, leading to a change of the shape of the bands and a shrinking of the difference between the two bands. Inclusion of the on-site inter-orbital hopping suppresses the so-called orbital-selective Mott transition.

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Qingguo Feng, Peter M. Oppeneer. 2011-10-18. Investigation of on-site inter-orbital single electron hoppings in general multi-orbital systems. https://doi.org/10.1103/physrevb.86.035107

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