Magnetic Order and Charge Disproportionation in a Spin-ice type Kondo Lattice Model: Large Scale Monte Carlo Study

TL;DR

This study uses large-scale Monte Carlo simulations to explore the phase diagram of a spin-ice type Kondo lattice model, revealing new magnetic and charge-ordered phases and their controllability via magnetic fields.

Contribution

It introduces a comprehensive phase diagram for the model, identifying a novel 32-sublattice phase with charge disproportionation and demonstrating field-induced switching of spin-charge patterns.

Findings

Discovery of a 32-sublattice magnetic phase with charge disproportionation

Identification of multiple magnetic orders including two-in two-out and all-in/all-out

Demonstration of magnetic field control over spin and charge configurations

Abstract

Phase diagram of a spin-ice type Kondo lattice model, potentially relevant to metallic pyrochlore oxides, is obtained by the Monte Carlo simulation implementing the polynomial expansion technique up to the system size with 2048 sites. We identified a new 32-sublattice magnetic phase with concomitant charge disproportionation, along with other phases such as two-in two-out and all-in/all-out orders. The spin and charge pattern can be switched by external magnetic field to a different one accompanied by a half magnetization plateau.