Magnetic properties of Yb23Cu7Mg4-type {Gd, Tb}23Ni7In4 compounds

The polycrystalline Yb23Cu7Mg4-type {Gd, Tb}23Ni7In4 compounds (space group P63/mmc, N 194, hP68) were prepared by arc melting with following annealing. They exhibit ferromagnetic ordering below Curie temperature TC = 142 K for Gd23Ni7In4 and TC = 112 K for Tb23Ni7In4, respectively. A field-sensitive antiferromagnetic transformation takes place around 90 K in Gd23Ni7In4 and 106 K in Tb26Ni7In4, respectively. Down to 10 K, they are soft ferromagnets with magnetizations of 4.7 μB/Gd for Gd23Ni7In4 and 5.7 μB/Tb for Tb23Ni7In4 in 90 kOe. In a field change of 50 kOe around TC, Gd23Ni7In4 shows magnetic entropy change of −4.7 J/kg⋅K at 133–143 K, while Tb23Ni7In4 shows magnetic entropy change of −5.4 J/kg⋅K at 109 K. The magnetic ordering and magnetocaloric effects of arc-melted polycrystalline Yb23Cu7Mg4-type {Gd, Tb}23Ni7In4 compounds (space group P63/mmc, N 194, hP68) have been investigated using magnetic measurements in fields up to 90 kOe. They exhibit ferromagnetic ordering below Curie temperature TC = 142 K for Gd23Ni7In4 and TC = 112 K for Tb23Ni7In4, respectively. A field-sensitive antiferromagnetic transformation takes place around 90 K in Gd23Ni7In4 and 106 K in Tb26Ni7In4, respectively. Down to 10 K, they are soft ferromagnets with magnetizations of 4.7 μB/Gd for Gd23Ni7In4 and 5.7 μB/Tb for Tb23Ni7In4 in 90 kOe. In a field change of 50 kOe around TC, Gd23Ni7In4 shows magnetic entropy change of −4.7 J/kg⋅K at 133–143 K, while Tb23Ni7In4 shows magnetic entropy change of −5.4 J/kg⋅K at 109 K. [Display omitted] •Yb23Cu7Mg4-type Gd23Ni7In4 and Tb23Ni7In4 prepared via arc-furnace melting/annealing.•Gd23Ni7In4 shows ferromagnetic ordering at 142 K and Tb23Ni7In4 at 112 K.•They exhibit field sensitive LT antiferromagnetic-like transformation of magnetic ordering.•Down to 10 K, these compounds are soft non-collinear ferromagnets in fields up to 90 kOe.•Gd23Ni7In4 has magnetic entropy change of −4.7 J/kg⋅K around TC (field change 0-50 kOe).•Tb23Ni7In4 shows magnetic entropy change of −5.4 J/kg⋅K at TC (field change 0-50 kOe).