Structural, electronic and magnetic properties of electron-doped CrAs

We report the effect of electron doping in binary transition metal-pnictide compound CrAs in polycrystalline compositions (Cr _0.85 T _0.15)As ( T = Fe, Co, Ni). Room temperature powder x-ray diffraction measurements show that the impurity-free doped samples crystallize in the orthorhombic MnP-type crystal structure with space group Pnma. Electrical resistivity ρ( T) data of all three compositions exhibit metallic behaviour with the room temperature ρ of about 1 mΩ cm, which is close to the values observed in single-crystal and polycrystalline samples of CrAs. Magnetic susceptibility χ( T) data of all three compositions show paramagnetic behaviour and show no evidence any magnetic ordering down to 1.8 K. The ρ( T) and χ( T) results collectively reveal that the antiferromagnetic ordering observed at Néel temperature T _N ≈ 270 K in CrAs is absent in the doped samples.