Co₂MnAl_1-xSi_xホイスラー合金の磁気抵抗効果

抄録

The composition dependence of the magnetoresistance, resistivity, magnetization, and crystal structure were investigated for Co₂MnAl_1-xSi_x and A₂MnAl(A = Fe-Co, Co-Ni) Heusler alloys prepared by the rapid quenching method. The crystal structure of the alloys was B2 structure except for Co₂MnSi, which was L2₁ structure. Both GMR and AMR were observed in several alloys. The GMR exhibited a maximum at x = 0.2 and A = Fe_0.1Co_0.9. The sign of the AMR was negative in several alloys. The composition dependence of the magnetoresistance, resistivity, and magnetization was calculated by using a simple model taking account of the reported DOS. The composition dependence of GMR and AMR is discussed.