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arXiv · 1812.04757

Quasiperiodicity and valence fluctuation in the spin-1/2 Falicov-Kimball model

Joji Nasu·Ryu Shinzaki·Akihisa Koga
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Abstract

We study the spin-1/2 Falicov-Kimball model with conduction and localized $f$ electrons on the Penrose lattice using the real-space dynamical mean-field theory. By changing the $f$ electron level, the $f$ electron density at each site changes continuously, in contrast to periodic systems with first-order valence transitions. In the intermediate valence regime, the local $f$ electron number strongly depends on a wider range of the Penrose structure surrounding its lattice site, in spite of the local interaction between the conduction and $f$ electrons. The temperature dependence of the magnetic response is also discussed.

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Joji Nasu, Ryu Shinzaki, Akihisa Koga. 2018-12-12. Quasiperiodicity and valence fluctuation in the spin-1/2 Falicov-Kimball model. https://doi.org/10.1007/s10909-018-02127-w

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