Exploring Frustration and Dynamic Magnetism in the Triangular Lattice Compound TbBO₃

Geometrically frustrated magnets are fertile ground for emergent quantum phenomena, ranging from macroscopically degenerate classical spin liquids to fractionalised excitation host quantum spin liquids. Many of these implementations are accomplished in three-dimensional pyrochlores or layered Kagome materials, but two-dimensional triangular lattices are a very clean system with which to experiment with frustration and anisotropy interaction. The recently realised synthesis of TbBO₃ offers a highly advantageous new avenue in this regard. Unlike other recently polymorphs, our TbBO₃ crystallises in the P6₃/m space group with an ideal triangular array of Tb³⁺ ions. Magnetic susceptibility and heat capacity measurements establish extensive antiferromagnetic correlations (θCW ≈ –8 K) but no indication of long-range magnetic order or spin freezing down to 1.8 K, indicating frustration and persistent spin dynamics. The integrity of the effective moment across temperature regimes also emphasises the contribution of spin–orbit coupling and single-ion anisotropy in determining low-energy magnetism. In combination, these results propose TbBO₃ as an two-dimensional rare-earth triangular lattice system at the cusp between classical and quantum spin-liquid behavior. We report here on our continuing investigations to detail its magnetic correlations and field-evolved phases, setting TbBO₃ as a platform for investigating frustration-driven dynamics in low-dimensional rare-earth magnets.