Raman scattering signatures of spinons and triplons in frustrated antiferromagnets

TL;DR

This paper demonstrates that magnetic Raman scattering can detect spinons in frustrated antiferromagnets, providing a way to distinguish topologically trivial from non-trivial quantum spin liquids.

Contribution

The study shows that spinons from one-dimensional physics produce identifiable signatures in Raman scattering, validated by calculations and experimental data on Ca$_3$ReO$_5$Cl$_2$.

Findings

Raman scattering signatures of spinons are clearly identifiable.

Calculated Raman intensity matches experimental measurements.

Spinons can be detected in frustrated antiferromagnets using Raman spectroscopy.

Abstract

Magnetically frustrated spin systems compose a significant proportion of topological quantum spin liquid candidates. Evidence for spin liquids in these materials comes largely from the detection of fractionalised spin-1/2 quasiparticles, known as spinons. However, the one-dimensional Heisenberg chain, which is topologically trivial, also hosts spinons. Thus, observing spinons does not necessarily signify long-range entanglement. Here, we show that spinons arising from one-dimensional physics leave a clear fingerprint in magnetic Raman scattering. We achieve this by calculating the magnetic Raman intensity of coupled Heisenberg chains. Our findings are in excellent agreement with the magnetic Raman scattering measurements on the anisotropic triangular antiferromagnet Ca$_3$ReO$_5$Cl$_2$.