Appearance of the superconducting phase transition of solders in magnetoresistance measurements

We have examined the influence of the superconducting phase transition in the solder materials Rose-metal (Bi-52.5%, Pb-32%, Sn-15.5%), CdIn alloy (Cd-50%, In-50%), and indium on magnetoresistance measurements of (Cd1−xMnx)3As2 . The superconducting phase transition of these solders takes place within the temperature and magnetic field ranges where quantum oscillations of magnetoresistance usually are observed. The appearance of the generated anomalous signals may lead to misinterpretation, in terms of anomalous oscillations of the magnetoresistance or quantization of the surface impedance. We have found a correlation between the magnitude of the anomalous signals and the resistivity ratio of solder and sample material.