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

TL;DR

This paper investigates how valence fluctuations and electric properties behave in the extended Anderson model on a 2D Penrose lattice, revealing unique valence distributions and coexistence of states due to lattice quasiperiodicity.

Contribution

It introduces a study of valence fluctuations in a quasiperiodic lattice using advanced theoretical methods, highlighting novel coexistence phenomena not seen in periodic systems.

Findings

Valence transition is absent; crossover occurs instead.

Nontrivial valence distributions emerge in the Penrose lattice.

Electric reconstruction occurs in the mixed valence region.

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.