Hidden glassy behaviors in an ideal Heisenberg Kagomé antiferromagnet

Abstract

Dynamics of classical Heisenberg spins, ${\mathbf{S}}_i=({\mathbf{s}}_i,S_{iz})$, on the Kagomé lattice has been studied. An ideal Heisenberg Kagomé antiferromagnet is known to remain disordered down to T=0 due to the macroscopic degeneracy of the ground state. Through the study, however, we find that ${\mathbf{S}}_i$ and their planar components ${\mathbf{s}}_i$ behave in a qualitatively different way and especially planar spins (${\mathbf{s}}_i$) show the exotic glass-like transition in the very low temperature $T\sim 0.003J$ ($J$: spin exchange). The glassy behaviors of ${\mathbf{s}}_i$ would be found to be driven by the spin-nematic fluctuations, different from ordinary spin glasses by disorders or anisotropies.

4 pages, 5 figures