Persistent Spin Dynamics in the Ising Triangular-lattice Antiferromagnet Ba$_6$Nd$_2$Ti$_4$O$_{17}$

TL;DR

This study investigates Ba$_6$Nd$_2$Ti$_4$O$_{17}$, a disorder-free triangular-lattice antiferromagnet, revealing persistent spin dynamics and absence of long-range order down to very low temperatures, suggesting a possible quantum spin liquid state.

Contribution

It provides experimental evidence of persistent spin dynamics and lack of magnetic order in an Ising triangular-lattice antiferromagnet, indicating potential quantum spin liquid behavior.

Findings

No long-range magnetic order down to 30 mK

Effective spins are Ising-like

Persistent spin dynamics observed at low temperatures

Abstract

We report results of magnetic susceptibility, specific heat, and muon spin relaxation ($\mu$SR) measurements on the polycrystalline Ba$_6$Nd$_2$Ti$_4$O$_{17}$, a disorder-free triangular-lattice antiferromagnet. The absence of long-range magnetic order or spin freezing is confirmed down to 30~mK, much less than the Curie-Weiss temperature -1.8~K. The magnetic and specific heat measurements reveal the effective-1/2 spins are Ising-like. The persistent spin dynamics is determined down to 37~mK. Our study present a remarkable example of Ising spins on the triangular lattice, which remains magnetically disordered at low temperatures and potentially hosts a quantum spin liquid ground state.