Anisotropy in Magnetic Phase Diagram of TbB2C2 with Field-Induced Antiferroquadrupolar Order

Abstract

The field-direction dependence of the magnetic phase diagram was examined for the compound TbB 2 C 2 with field-induced antiferroquadrupolar-ordering, in order to elucidate anisotropy in the magnetic phase diagrams for H ∥[1 0 0] and H ∥[1 1 0]. The field-induced phase for H ∥[1 0 0] (phase III), which is a phase in which antiferromagnetic (AFM) and antiferroquadrupolar (AFQ) orders coexist, seems to change continuously into the other (AFQ + AFM) phase (phase II ′ ) for H ∥[1 1 0]. The result implies that both III and II ′ phases have some similarity in their magnetic structures or they are possibly the same as each other.