Linear response theoretical study of the exchange interactions in Mn-doped ScN: Effects of disorder, band gap, and doping

Linear response calculations of the magnetic exchange interactions in Mn-doped ScN were carried out in the rigid-spin approximation by using the muffin-tin-orbital Green's function method. They show that the exchange interactions are long range and strongly affected by disorder, band gap corrections, and doping. The cluster variation method is shown to reduce the T-c by about 30% as compared to the mean-field treatment. A Curie temperature saturating with Mn concentration above 20% at similar to 440 K is predicted with a semiconducting behavior present until about 15%. Both p- and n-type doping are found to decrease T-c.