ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Neutron diffraction techniques have been used to investigate the magnetic ordering of the Tb ions in polycrystalline Pb2Sr2TbCu3O8. Significant magnetic correlations are found to develop below ∼10 K, and these correlations are two dimensional in nature, representative of the strongly anisotropic magnetic interactions in these layered materials. The correlation length increases with decreasing temperature, and long-range order is observed to develop at TN≈5.5 K. However, the sawtooth Bragg profile for the scattering demonstrates that the long-range order is two dimensional, rather than three dimensional, with a spin configuration where nearest-neighbor spins are antiparallel. The scattering profile can be explained quantitatively by assuming long-range order within the ab plane, with no significant correlations along the c axis to the lowest temperatures measured (1.36 K). Our results suggest that the system is well described by a two-dimensional Ising model. The only other (pure) system where a crossover to three-dimensional behavior is not observed is DyBa2Cu4O8.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.356907
