Magnetic excitations in a new anisotropic Kagom\'{e} antiferromagnet

TL;DR

This study investigates the magnetic excitations in Nd-langasite, a kagome antiferromagnet, revealing unusual dispersive features and short-range correlations consistent with a potential spin liquid state.

Contribution

It provides the first experimental evidence of magnetic excitations and possible spin liquid behavior in an anisotropic kagome antiferromagnet.

Findings

Unusual dispersive magnetic excitations observed

Short-range magnetic correlations identified

Evidence supporting a spin liquid state

Abstract

The Nd-langasite compound contains planes of magnetic Nd3+ ions on a lattice topologically equivalent to a kagom\'{e} net. The magnetic susceptibility does not reveal any signature of long-range ordering down to 2 K but rather a correlated paramagnetism with significant antiferromagnetic interactions between the Nd and a single-ion anisotropy due to crystal field effect. Inelastic neutron scattering on Nd-langasite powder and single-crystal allowed to probe its very peculiar low temperature dynamical magnetic correlations. They present unusual dispersive features and are broadly localized in wave-vector Q revealing a structure factor associated to characteristics short range-correlations between the magnetic atoms. From comparison with theoretical calculations, these results are interpreted as a possible experimental observation of a spin liquid state in an anisotropic kagom\'{e} antiferromagnet.