Hidden quantum spin liquid behavior confirmed in a new kagome crystal

The article reports a significant advancement in confirming the existence of quantum spin liquids (QSLs), an exotic state of matter where electron spins remain in a fluctuating, entangled state even near absolute zero, defying typical magnetic order. Historically elusive due to their lack of clear experimental signatures, QSLs have been difficult to conclusively identify. The research team focused on materials with a kagome lattice—a triangular atomic pattern known to frustrate magnetic order and potentially host QSLs. Previously, unusual magnetic excitations observed in the kagome material herbertsmithite hinted at QSL behavior, but it was unclear if these were unique to that compound. To address this, the researchers synthesized high-quality single crystals of a different kagome material, Zn-barlowite, and used inelastic neutron scattering at very low temperatures to probe its spin dynamics. They discovered that the fundamental excitations in Zn-barlowite were not conventional magnons but fractionalized spinons, a hallmark of strong quantum ent