Polarized neutron scattering studies of the kagome lattice antiferromagnet KFe[subscript 3](OH)[subscript 6](SO[subscript 4])[subscript 2]

[摘要] We report polarized neutron scattering studies of spin-wave excitations and spin fluctuations in the S = 5/2 kagome lattice antiferromagnet KFe[subscript 3](OH)[subscript 6](SO[subscript 4])[subscript 2] (jarosite). Inelastic polarized neutron scattering measurements at 10 K on a single crystal sample reveal two spin gaps, associated with in-plane and out-of-plane excitations. The polarization analysis of quasi-elastic scattering at 67 K shows in-plane spin fluctuations with XY symmetry, consistent with the disappearance of the in-plane gap above the Neel temperature T[subscript N] = 65 K. Our results suggest that jarosite is a promising candidate for studying the 2D XY universality class in magnetic systems.

[发布机构] Elsevier