Tuesday, June 25, 2013

1306.5244 (W. S. Oliveira et al.)

Mott-Anderson transition in the disordered charge transfer model    [PDF]

W. S. Oliveira, M. C. O. Aguiar, V. Dobrosavljevic
In this paper we consider the charge-transfer (CT) model, which incorporates the charge-transfer nature and as such can give a better description of Mott systems than the single-band Hubbard model. The disordered version of the model is solved by us using an extension of dynamical mean field theory able to describe Anderson localization effects. Our current results are in surprisingly good agreement with those recently obtained by two of us with a more sophisticated treatment; moreover, the current calculation allows us to better characterize the approach to the metal-insulator transitions. According to our present results, as the interaction induced transition is approached, a fraction of sites turn into local moment, but not all of them do it, in contrast to previous results for the Hubbard model, where all sites Mott localize close to the transition. The approach to the disorder driven transition is also qualitatively different than for the Hubbard model: although in the two models part of the sites Anderson localize, for the Hubbard model all the remaining ones turn into local moments, while for the CT model none of them do it.
View original: http://arxiv.org/abs/1306.5244

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