Coexistence and interaction of spinons and magnons in an antiferromagnet with alternating antiferromagnetic and ferromagnetic quantum spin chains

TL;DR

This paper reports the discovery of coexistence and interaction of magnons and spinons in a unique quantum antiferromagnet with alternating ferromagnetic and antiferromagnetic chains, challenging traditional energy regime distinctions.

Contribution

It introduces a new quantum antiferromagnet system where magnons and spinons coexist and interact, providing a novel platform for studying different magnetic quasiparticles.

Findings

Magnons and spinons coexist in the material.

Interactions between magnons and spinons are observed.

The system offers a new paradigm for quasiparticle interaction studies.

Abstract

In conventional quasi-one-dimensional antiferromagnets with quantum spins, magnetic excitations are carried by either magnons or spinons in different energy regimes: they do not coexist independently, nor could they interact with each other. In this Letter, by combining inelastic neutron scattering, quantum Monte Carlo simulations and Random Phase Approximation calculations, we report the discovery and discuss the physics of the coexistence of magnons and spinons and their interactions in Botallackite-Cu2(OH)3Br. This is a unique quantum antiferromagnet consisting of alternating ferromagnetic and antiferromagnetic Spin-1/2 chains with weak inter-chain couplings. Our study presents a new paradigm where one can study the interaction between two different types of magnetic quasiparticles, magnons and spinons.