Superconducting readout of current-induced magnetization switching

Abstract

We demonstrate a superconducting readout method for detecting current-induced magnetization switching of a polycrystalline cobalt wire, based on the measurement of the critical current of an adjacent superconducting aluminum wire. The critical current Ic of this superconductor–superconductor/ferromagnet–superconductor junction is highly dependent on the magnetization state of the ferromagnet, reflected in its local stray-field distribution. This dependency allows for a detection of changes in the magnetization of the ferromagnet while no current passes through it during readout. Furthermore, we present micromagnetic simulations replicating our observations, thereby visualizing the microscopic switching behavior in polycrystalline Co.