Influence of quantum fluctuations on the magnetic properties of quasi-one-dimensional triangular antiferromagnets

A review is presented of the experimental work on the influence of quantum fluctuations on the magnetization and the mean spin of magnetic sublattices in quasi-one-dimensional triangular antiferromagnets. The principal result s in this area are the strong magnetic-field dependence of magnetic sublatt ice mean spins; anisotropy in mean spin values in magnetically nonequivalen t antiferromagnetic chains; the reduction of magnetization compared to the classical spin case; the nonlinear growth of the parallel magnetic suscepti bility; a residual magnetization anisotropy at high fields. The results obt ained are explained based on the spin-wave theory of the quantum fluctuatio ns in antiferromagnets. A new magnet observed in CsMnI3 for H parallel to C -6 and shown to be due to the anisotropy of the mean spins of the sublattic es.