Hierarchy of magnon entanglement in antiferromagnets

TL;DR

This paper investigates the hierarchy of magnon entanglement in antiferromagnets with Dzyaloshinskii-Moriya interaction, revealing how entanglement depends on lattice factors and interaction ratios, and proposing detection methods.

Contribution

It introduces a hierarchy of magnon entanglement in antiferromagnets and links it to specific lattice and interaction parameters, with implications for experimental detection.

Findings

Magnon entanglement hierarchy established in antiferromagnets.

Entanglement depends on lattice-specific factors and interaction ratios.

Long wavelength magnon modes exhibit the highest entanglement.

Abstract

Continuous variable entanglement between magnon modes in Heisenberg antiferromagnet with Dzyaloshinskii-Moryia (DM) interaction is examined. Different bosonic modes are identified, which allows to establish a hierarchy of magnon entanglement in the ground state. We argue that entanglement between magnon modes is determined by a simple lattice specific factor, together with the ratio of the strengths of the DM and Heisenberg exchange interactions, and that magnon entanglement can be detected by means of quantum homodyne techniques. As an illustration of the relevance of our findings for possible entanglement experiments in the solid state, a typical antiferromagnet with the perovskite crystal structure is considered, and it is shown that long wave length magnon modes have the highest degree of entanglement.