Possible spin-liquid state in the rare-earth based kagome antiferromagnet

The interplay between spin-orbit coupling, spin correlation, and crystal electric field in rare-earth-based geometrically frustrated magnets offers a promising ground for the search for enigmatic quantum spin liquids (QSL). QSL is a highly entangled state ideal to host fractional excitations coupled to emergent gauge fields and has immense potential for braiding quantum computing technology. However, the experimental realization of QSL is a challenging theme due to the presence of defect and disorder in real quantum materials. Here, we focus on a new rare-earth-based spin-lattice Pr3BWO9 wherein Pr3+ ions constitute a two-dimensional corner shared triangles decorating a kagome quantum magnet. Neither magnetic susceptibility nor specific-heat data show any signature of long-range magnetic ordering or spin freezing down to 70 mK despite a sizable Curie-Weiss temperature of θcw = - 6.8 K. This calls for more sensitive local-probe magnetic investigations that could unambiguously confirm the spin-liquid ground state and characterize the corresponding magnetic excitations at very low temperature given the rather weak exchange coupling between Pr3+ moments. We propose a µSR study at sub-kelvin temperatures to provide valuable insight and confirm the spin-liquid conjecture in this novel rare-earth-based kagome lattice antiferromagnet family and to explore the role of rare-earth ions on the quantum-disordered state.