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

TL;DR

This study uses Monte Carlo simulations to explore a Kondo lattice model on a triangular lattice, revealing a unique partial disorder phase stabilized by spin-charge interactions, with implications for magnetic and electronic properties.

Contribution

It uncovers a novel partial disorder phase in an Ising-spin Kondo lattice model, driven by nonperturbative spin-charge interplay on a triangular lattice.

Findings

Identification of a stable partial disordered phase near 1/3-filling.

Coexistence of magnetic order and paramagnetic moments in the phase.

Charge order and electronic gap development associated with the phase.

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.