Preparation of Anomalous Magnetoresistance and Transport Properties of Itinerant Ferromagnet Fe1–xCoxSi

DC magnetization, electrical transport, and magnetoresistance (MR) measurements of Fe
_1-x
Co
_x
Si single crystals with x ≈ 0.7-0.3 are reported. Fe
_1-x
Co
_x
Siseries presents a typical Stoner band excitation characteristic in the field-dependent magnetization profile. Co-doping (x > 0.3) in the Fe
_1-x
Co
_x
Si compound shows a semiconductor-to-metal transition. Enhanced positive MR has been observed when ~1/3 of the Fe was substituted with Co, which suggests that the spin density of states in the minor band (semiconductor characteristic) dominates the electronic properties.