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arXiv · 1502.03907

Valence Fluctuations and Electric Reconstruction in the Extended Anderson Model on the Two-Dimensional Penrose Lattice

Shinichi Takemura·Nayuta Takemori·Akihisa Koga
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Abstract

We study the extended Anderson model on the two-dimensional Penrose lattice, combining the real-space dynamical mean-field theory with the non-crossing approximation. It is found that the Coulomb repulsion between localized and conduction electrons does not induce a valence transition, but the crossover between the Kondo and mixed valence states in contrast to the conventional periodic system. In the mixed-valence region close to the crossover, nontrivial valence distributions appear characteristic of the Penrose lattice, demonstrating that the mixed-valence state coexists with local Kondo states in certain sites. The electric reconstruction in the mixed valence region is also addressed.

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Shinichi Takemura, Nayuta Takemori, Akihisa Koga. 2015-02-13. Valence Fluctuations and Electric Reconstruction in the Extended Anderson Model on the Two-Dimensional Penrose Lattice. https://doi.org/10.1103/physrevb.91.165114

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