Magnetic diffuse scattering investigation in the spin liquid candidate on a stuffed honeycomb lattice:TbBO3

Quantum spin liquid (QSL) represents a highly entangled state of matter characterized by the absence of long-range magnetic order, despite strong exchange interactions between its magnetic constituents. QSLs are ideal hosts of exotic fractional excitations coupled to emergent gauge fields and potential applications in fault-tolerant quantum computing. The experimental realization of QSLs remains elusive owing to defects and anti-site disorder in real materials. Our focus is on a “stuffed honeycomb lattice” frustrated rare-earth TbBO3 comprised of a honeycomb lattice with a superimposed triangular lattice formed by additional magnetic ions at the center of each hexagon, that can support exotic quantum phenomena, including elusive Dirac QSL with fractional excitations. Our muon experiments down to 16 mK rule out magnetic ordering and spin freezing supported by ac susceptibility down to 50 mK. Specific heat down to 100 mK shows no signature of magnetic ordering and it shows power law behavior indicative of gapless spin excitations supported by NMR results. We plan to perform neutron diffraction on the WISH instrument via Rapid Access at sub-Kelvin temperatures to reveal the exact magnetic structure, shed insights into the ground state and the short-range spin correlations at low-T via diffuse neutron scattering. One paper was submitted to PRL on this material [12], which is nearly accepted, but one of the referees suggested diffuse scattering data of TbBO3 before acceptance.