Study of Magnetic Interactions in (SnTe–MnTe) and (SnTe–EuTe) Systems

As reported earlier the alloy system Sn0.97−xMnxTe orders ferromagnetically with Curie temperatures varying linearly with x. The present work has extended this and includes: (i) More superconductivity results which indicate that for low carrier densities (∼1021 cm−3), the paramagnetic impurity influences Tc very drastically, e.g., 100-ppm Mn destroys the superconductivity completely. However, if the carrier density is increased to 4×1021 cm−3, the transition temperature decreases gradually with increasing Mn content and superconductivity persists even for x=0.001. In both cases, however, the transition is broadened probably due the presence of the internal fields. (ii) Electrical resistivity measurements made on these samples (0.00001