The Kagome Antiferromagnet with Defects: Satisfaction, Frustration, and Spin Folding in a Random Spin System

TL;DR

This paper investigates how site disorder affects the magnetic states in a classical kagome antiferromagnet, revealing noncoplanar states, a novel spin origami mapping, and the absence of conventional spin glass behavior.

Contribution

It introduces a new spin origami mapping of ground states and shows disorder induces noncoplanar states without causing spin glass behavior.

Findings

Disorder induces noncoplanar states in the kagome AFM.

Ground state energy is additive over satisfied triangles.

No conventional spin glass behavior observed.

Abstract

It is shown that site disorder induces noncoplanar states, competing with the thermal selection of coplanar states, in the nearest neighbor, classical kagome Heisenberg antiferromagnet (AFM). For weak disorder, it is found that the ground state energy is the sum of energies of separately satisfied triangles of spins. This implies that disorder does not induce conventional spin glass behavior. A transformation is presented, mapping ground state spin configurations onto a folded triangular sheet (a new kind of ``spin origami'') which has conformations similar to those of tethered membranes.