Structures, magnetism and transport properties of the potential spin-gapless semiconductor CoFeMnSi alloy

The polycrystalline CoFeMnSi alloy with a potential spin gapless semiconductor (SGS) behavior was prepared by arc melting. The structures, magnetism and transport properties of CoFeMnSi alloy were investigated in detail. The occurrence of (1 1 1) superlattice XRD peak indicates the highly ordered Y-type structure of CoFeMnSi alloy. The saturation magnetization is around 3.49 μB/f.u. and the Curie temperature is about 763 K. The transport properties exhibit a semiconducting-like behavior and the resistivity is about 269 μΩ cm at 300 K. The carrier concentration almost shows a non-dependence of temperature, which is different from that of traditional semiconductor, presenting a typical characteristic of spin gapless semiconductor. The carrier concentration and carrier mobility measured at 300 K are 4.9 × 1020 cm−3 and 46 cm2/V.s, respectively.