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arXiv · 1309.5167

Monte Carlo Study of an Effective Ising Model for the Spin-ice type Kondo Lattice Model

Hiroaki Ishizuka·Masafumi Udagawa·Yukitoshi Motome
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Abstract

An effective Ising model for the spin-ice type Kondo lattice model is investigated by the classical Monte Carlo simulation. We clarify the magnetic phase diagram with four phases: ice-ferro, ice-(0,0,2π), 32-sublattice, and all-in/all-out ordered states. The result well reproduces the phase diagram of the Kondo lattice model studied previously [H. Ishizuka et al.: J. Phys. Soc. Jpn. 81 (2012) 113706], which suggests that the RKKY interactions up to third neighbors are sufficient to describe the magnetic properties of the itinerant electron model. We discuss the peculiar nature of phase transitions: the suppression of the critical temperatures down to zero temperature between two ice phases and the presence of the tricritical points on the phase boundary of the 32-sublattice ordered state.

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Hiroaki Ishizuka, Masafumi Udagawa, Yukitoshi Motome. 2013-09-20. Monte Carlo Study of an Effective Ising Model for the Spin-ice type Kondo Lattice Model. https://doi.org/10.7566/jpscp.3.014013

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