Electrical response of superconductor/ferromagnet/topological-insulator/superconductor junctions to magnetic texture dynamics

Abstract

We consider a hybrid structure consisting of superconducting or normal leads with a combined ferromagnet-3D topological insulator interlayer. We compare responses of a Josephson junction and a normal junction to magnetic texture dynamics. In both cases the electromotive force resulting from the magnetization dynamics generates a voltage between the junction leads. For an open circuit this voltage is the same for normal and superconducting leads and allows for electrical detection of magnetization dynamics and a structure of a given magnetic texture. However, under the applied current the electrical response of the Josephson junction is essentially different due to the strong dependence of the critical Josephson current on the magnetization direction and can be used for experimental probing of this dependence. We propose a setup, which is able to detect a defect motion and to provide detailed information about the structure of magnetic inhomogeneity. The discussed effect could be of interest for spintronics applications.