Magnetic anisotropy of Tb1−xGdxMn6Sn6 compounds

Magnetization curves of Tb_1−xGd_xMn₆Sn₆ compounds (0?x?1) have been measured for aligned powder samples in the temperature range 4.2–300 K in pulsed magnetic fields up to 30 T. Temperature and concentration dependences of the magnetocrystalline anisotropy constants K₁ and K₂ and concentration dependence of the temperature of spontaneous spin-reorientation transition have been determined. Using these data, we estimated the contribution of the manganese and terbium atoms to the magnetic anisotropy of Tb_1−xGd_xMn₆Sn₆ and analyzed the origin of the appearance of field-induced first-order magnetic phase transition in these compounds.