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arXiv · 1008.3666

Effective Low-Energy Model for f-Electron Delocalization

K. A. Al-Hassanieh·Yi-feng Yang·Ivar Martin·C. D. Batista
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Abstract

We consider a Periodic Anderson Model (PAM) with a momentum-dependent inter-band hybridization that is strongly suppressed near the Fermi level. Under these conditions, we reduce the PAM to an effective low-energy Hamiltonian, $H_{\rm eff}$, by expanding in the small parameter $V_0/t$ ( $V_0$ is the maximum inter-band hybridization amplitude and $t$ is the hopping integral of the broad band). The resulting model consists of a t-J f-band coupled via the Kondo exchange to the electrons in the broad band. $H_{\rm eff}$ allows for studying the f-electron delocalization transition. The result is a doping-induced Mott transition for the f-electron delocalization, which we demonstrate by density-matrix renormalization group (DMRG) calculations.

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K. A. Al-Hassanieh, Yi-feng Yang, Ivar Martin, C. D. Batista. 2010-08-21. Effective Low-Energy Model for f-Electron Delocalization. https://doi.org/10.1103/physrevlett.105.086402

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