High field magnetism of the quasi one-dimensional anisotropic antiferromagnet BaCo2V2O8

We have performed high field magnetization measurements on the quasi onedimensional (1D) antiferromagnet BaCo2V2O8, which shows a curious field-induced orderdisorder transition, in pulsed magnetic fields up to 55 T. The observed magnetization curves up to the saturation field show non-linear increases, suggesting a strong quantum fluctuation. We analyze the magnetization curves in terms of the S = 1/2 1D XXZ model.