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arXiv · 1406.6292

Interorbital interaction in the one-dimensional periodic Anderson model: A density-matrix renormalization-group study

I. Hagymasi·J. Solyom·O. Legeza
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Abstract

We investigate the effect of the Coulomb interaction, $U_{cf}$, between the conduction and f electrons in the periodic Anderson model using the density-matrix renormalization-group algorithm. We calculate the excitation spectrum of the half-filled symmetric model with an emphasis on the spin and charge excitations. In the one-dimensional version of the model it is found that the spin gap is smaller than the charge gap below a certain value of $U_{cf}$ and the reversed inequality is valid for stronger $U_{cf}$. This behavior is also verified by the behavior of the spin and density correlation functions. We also perform a quantum information analysis of the model and determine the entanglement map of the f and conduction electrons. It is revealed that for a certain $U_{cf}$ the ground state is dominated by the configuration in which the conduction and f electrons are strongly entangled, and the ground state is almost a product state. For larger $U_{cf}$ the sites are occupied alternatingly dominantly by two f electrons or by two conduction electrons.

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I. Hagymasi, J. Solyom, O. Legeza. 2014-09-24. Interorbital interaction in the one-dimensional periodic Anderson model: A density-matrix renormalization-group study. https://doi.org/10.1103/physrevb.90.125137

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