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arXiv · 1207.0381

Hubbard physics in the symmetric half-filled periodic Anderson-Hubbard model

I. Hagymasi·K. Itai·J. Solyom
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Abstract

Two very different methods -- exact diagonalization on finite chains and a variational method -- are used to study the possibility of a metal-insulator transition in the symmetric half-filled periodic Anderson-Hubbard model. With this aim we calculate the density of doubly occupied $d$ sites as a function of various parameters. In the absence of on-site Coulomb interaction ($U_f$) between $f$ electrons, the two methods yield similar results. The double occupancy of $d$ levels remains always finite just as in the one-dimensional Hubbard model. Exact diagonalization on finite chains gives the same result for finite $U_f$, while the Gutzwiller method leads to a Brinkman-Rice transition at a critical value ($U_d^c$), which depends on $U_f$ and $V$.

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I. Hagymasi, K. Itai, J. Solyom. 2012-07-02. Hubbard physics in the symmetric half-filled periodic Anderson-Hubbard model. https://doi.org/10.3938/jkps.62.1423

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