Electrical resistivity in Co-rich pseudobinary Ni-Cr ferromagnetic metallic glasses from 1.5 to 300 K

摘要

Electrical resistivity ρ(T) has been measured in two series of melt-spun amorphous ferromagnets Fe_5Co_(50)Ni_(17-x)C_rxB_(16)Si_(12) (x=0,5,10,15) and Fe_(7.8)Co_(31.2)Ni_(39-x)Cr_xB_(14)Si_8 (x=5,10,15) and Fe_(7.8)Co_(31.2)Ni_(24)Mn_(15)B_(14)Si_8 between 1.5 and 25 K. ρ(T) of all these high-resistive, soft ferromagnetic samples with wide device applications show pronounced minima at T_(min). In the region well below T_(min), it shows very conclusively a (- T~(1/2)) dependence coming from electron-electron interaction effects in the presence of weak localization due to their high structural disorder. ρ(T), measured over a wider temperature range of 1.5-300 K in the second series, shows in the region well above T_(min) a T~2 dependence coming from either the dynamical structure factor or magnetic scattering or from both. At still higher temperatures, ρ(T) ～ T through the structural term only. The above interpretation is severely restricted by various characteristic temperatures such as Debye, Curie, and T_(min) in the relevant theories used for the analysis. Reasonable isolations of different contributions were only possible because of the very high resolution of the ρ(T) data.