Synthesis and characterization of magnetic (Cr0.5Mn0.5)2GaC thin films

Growth of (Cr0.5Mn0.5)(2)GaC thin films from C, Ga, and compound Cr0.5Mn0.5 targets is reported for depositions on MgO (111), 4H-SiC (0001), and Al2O3 (0001) with and without a NbN (111) seed layer. Structural quality is found to be highly dependent on the choice of substrate with MgO (111) giving the best results as confirmed by X-ray diffraction and transmission electron microscopy. Phase pure, high crystal quality MAX phase thin films are realized, with a Cr:Mn ratio of 1:1. Vibrating sample magnetometry shows a ferromagnetic component from 30 K up to 300 K, with a measured net magnetic moment of 0.67 mu(B) per metal (Cr + Mn) atom at 30 K and 5 T. The temperature dependence of the magnetic response suggests competing magnetic interactions with a resulting non-collinear magnetic ordering.