Impact of Stealthy Hyperuniform Magnetic Impurity Configurations on Bulk Magnetism in a Two-dimensional Heisenberg Model

TL;DR

This study explores how stealthy hyperuniform impurity arrangements in a 2D Heisenberg model affect bulk magnetism, revealing that triangular-like configurations enhance magnetization through sublattice effects.

Contribution

It introduces a method to generate and analyze stealthy hyperuniform impurity configurations and demonstrates their impact on magnetic properties using linear spin-wave theory.

Findings

Triangular-lattice-like arrangements increase average staggered magnetization.

Sublattice effects influence impurity pairing and magnetic enhancement.

Hyperuniform configurations can be tailored to optimize magnetic properties.

Abstract

We investigate an antiferromagnetic quantum Heisenberg model on a square lattice with high-spin magnetic impurities to clarify how random and stealthy hyperuniform impurity configurations influence the bulk magnetic properties. Stealthy hyperuniform configurations are generated using generalized cost functions that interpolate between square-lattice-like and triangular-lattice-like arrangements. Using linear spin-wave theory for the mixed-spin model, we demonstrate that triangular-lattice-like arrangements yield a larger average staggered magnetization than both random and square-lattice-like cases. This enhancement originates from sublattice effects: while the square-lattice-like configuration enforces nearest-neighbor impurities to occupy opposite sublattices due to its bipartite structure, the triangular-lattice-like arrangement allows same-sublattice nearest-neighbor pairs, thereby strengthening cooperative magnetic enhancement.