摘要
We have investigated the magneto-transport properties of an off-stoichiometric full-Heusler alloy Co_2MnAl single-crystalline film. The Co_(1.65)Mn_(1.35)Al(CMA) film epitaxially grown on Ⅲ–Ⅴ semiconductor GaAs substrate exhibits perpendicular magnetic anisotropy. The resistivity of the CMA film increases with the temperature T decreasing from 300 to 5 K, showing a semiconducting-like transport behavior. Different activation energies are found in three temperature regions with transition temperatures of 35 and 110 K. In the meanwhile, the remanent magnetization can be described by T^(3/2) and T^2 laws in the corresponding medium and high T ranges, respectively. The transition at around 110 K could be attributed to the ferromagnetism evolving from localized to itinerant state. The Curie temperature of the CMA film is estimated to be ～640 K. The intrinsic anomalous Hall conductivity of ～55 Ω^(-1) cm^(-1) is obtained, which is almost twenty times smaller than that of Co_2MnAl.
We have investigated the magneto-transport properties of an off-stoichiometric full-Heusler alloy Co_2MnAl single-crystalline film. The Co_(1.65)Mn_(1.35)Al(CMA) film epitaxially grown on Ⅲ–Ⅴ semiconductor GaAs substrate exhibits perpendicular magnetic anisotropy. The resistivity of the CMA film increases with the temperature T decreasing from 300 to 5 K, showing a semiconducting-like transport behavior. Different activation energies are found in three temperature regions with transition temperatures of 35 and 110 K. In the meanwhile, the remanent magnetization can be described by T^(3/2) and T^2 laws in the corresponding medium and high T ranges, respectively. The transition at around 110 K could be attributed to the ferromagnetism evolving from localized to itinerant state. The Curie temperature of the CMA film is estimated to be ～640 K. The intrinsic anomalous Hall conductivity of ～55 Ω^(-1) cm^(-1) is obtained, which is almost twenty times smaller than that of Co_2MnAl.
基金
supported by the Ministry of Science and Technology under Grant Nos.2015CB921500,2017YFB0405701
the National Natural Science Foundation of China under Grant Nos.U1632264 and 11704374
