Pressure Effect on the Curie Temperature of Ni₂In-Type (Mn_1-zFe_z) ₇Sn₄

Abstract

The variations of the Curie temperature T_c and ferrimagnetic moment n_f in (Mn_1-zFe_z) ₇Sn₄ (0≤z≤0. 35) have been investigated as functions of z and hydrostatic pressure P up to the maximum 12. 5kbar. Below z∼0. 25, T_c decreases with increasing z, but it increases above z∼0. 25. The pressure derivative of T_c, dT_c/dP decreases and n_f increases with increasing z below z∼0. 1 above which these values are nearly constant. These features are compared with the results of (Mn_1-uCo_u) ₇Sn₄ and Mn₇ (Sn_1-xGe_x) ₄ from the electronic and magnetic points of view.