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.
@article{arxiv.1205.5782,
title = {Emergence of a common energy scale close to the orbital-selective Mott transition},
author = {Markus Greger and Marcus Kollar and Dieter Vollhardt},
journal= {arXiv preprint arXiv:1205.5782},
year = {2013}
}