Altermagnetism in exactly solvable model: the Ising-Kondo lattice model

TL;DR

This paper demonstrates the existence and stability of altermagnetic phases, specifically d-wave AM, in an exactly solvable Ising-Kondo lattice model using Monte Carlo simulations, revealing key signatures and robustness of these phases.

Contribution

It introduces a theoretical framework for altermagnetism in the Ising-Kondo lattice model, showing the stability of d-wave AM phases under various conditions and confirming their symmetry properties.

Findings

Identification of AM-like states with spin-split bands

Demonstration of d-wave AM stability across parameters

Confirmation of d-wave symmetry via impurity analysis

Abstract

Altermagnet (AM), a recently identified class of collinear magnet, has garnered significant attention due to its unique combination of zero net magnetization and spin-split energy bands, leading to a variety of novel physical phenomena. Using numerically exact lattice Monte Carlo simulations, we investigate AM-like phases within the Ising-Kondo lattice model which is commonly employed to describe heavy-fermion materials. By incorporating an alternating next-nearest-neighbor hopping (NNNH) term, which arises from the influence of non-magnetic atoms in altermagnetic candidate materials, our results reveal key signatures of AM-like states, including spin-splitting quasiparticle bands and spectral functions, and demonstrate that d-wave AM remains stable across a broad range of interaction strengths, doping levels, NNNH amplitudes and temperatures, highlighting its robustness. Furthermore, through an analysis of non-magnetic impurity effects, we further confirm the d-wave symmetry of the AM phase. These findings establish a solid theoretical foundation for exploring AM-like phases in f-electron compounds, paving the way for future investigations into their exotic magnetic and electronic properties.