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arXiv · 1205.5782

Emergence of a common energy scale close to the orbital-selective Mott transition

Markus Greger·Marcus Kollar·Dieter Vollhardt
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Abstract

We calculate the spectra and spin susceptibilities of a Hubbard model with two bands having different bandwidths but the same on-site interaction, with parameters close to the orbital-selective Mott transition, using dynamical mean-field theory. If the Hund's rule coupling is sufficiently strong, one common energy scale emerges which characterizes both the location of kinks in the self-energy and extrema of the diagonal spin susceptibilities. A physical explanation of this energy scale is derived from a Kondo-type model. We infer that for multi-band systems local spin dynamics rather than spectral functions determine the location of kinks in the effective band structure.

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Markus Greger, Marcus Kollar, Dieter Vollhardt. 2012-05-25. Emergence of a common energy scale close to the orbital-selective Mott transition. https://doi.org/10.1103/physrevlett.110.046403

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