A proximate model material for triangular lattice quantum spin liquids

Neutron spectroscopy, entanglement analysis, and simulations provide evidence that KYbSe2 closely approximates a 2D quantum spin liquid. Although KYbSe2 displays magnetic ordering at low temperatures, its magnetic dynamics are dominated by fractionalized excitations that exhibit anomalously large quantum entanglement, indicating that on finite timescales KYbSe2 exhibits quantum spin liquid physics.