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arXiv · 1205.4826

Partial disorder in an Ising-spin Kondo lattice model on a triangular lattice

Hiroaki Ishizuka·Yukitoshi Motome
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Abstract

Phase diagram of an Ising-spin Kondo lattice model on a triangular lattice near 1/3-filling is investigated by Monte Carlo simulation. We identify a partially disordered phase with coexistence of magnetic order and paramagnetic moments, which was unstable in two-dimensional Ising models with localized spins only. The partial disorder emerges in the competing regime between a twosublattice stripe phase and three-sublattice ferrimagnetic phase, at finite temperatures above an electronic phase separation. The peculiar magnetic structure accompanies a charge order and develops a gap in the electronic structure. The results manifest a crucial role of the nonperturbative interplay between spin and charge degrees of freedom in stabilizing the partial disorder.

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Hiroaki Ishizuka, Yukitoshi Motome. 2012-05-22. Partial disorder in an Ising-spin Kondo lattice model on a triangular lattice. https://doi.org/10.1103/physrevlett.108.257205

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