Magnetic properties of single-crystalline TbFe5Al7

A TbFe5Al7 single crystal (tetragonal crystal structure of the ThMn12 type) has been studied in magnetic fields up to 14 T. The compound is a ferrimagnet with the Curie temperature TC = 242 K. A compensation of the Tb and Fe sublattices is observed at Tcomp = 84 K. TbFe5Al7 displays strong easy-plane anisotropy. Anisotropy is also present within the basal plane practically in the whole temperature range of the magnetically-ordered state. The easy magnetization direction is the [1 0 0] axis at low temperatures. A spin-reorientation transition occurs within the basal plane from [1 0 0] to [1 1 0], presumably in the vicinity of the compensation temperature. At T < Tcomp the compound displays field-induced magnetic transitions along the [1 0 0] axis, whereas at T > Tcomp there are transitions observed along the [1 1 0] axis. The critical fields Hcr of the transitions along both axes tend to zero upon approaching T = Tcomp. A diagram in the coordinates Hcr-T has been plotted for a magnetic field up to 14 T. At low temperatures very strong magnetic hysteresis is observed, a field of 14 T is not sufficiently strong to magnetize the sample at T = 2 K along the [1 0 0] axis.