Control of lateral ferromagnetic domains in Cr2O3/Pt/Co thin film system with positive exchange bias

We investigated the switching of perpendicular exchange bias (PEB) from a negative to a positive value in an exchange-coupled Cr2O3/Pt/Co heterostructure. With varying the Pt spacer layer thickness or the measurement temperature, two types of intermediate states were found during the switching process: a double hysteresis loop indicating a local PEB and a single hysteresis loop indicating an averaged PEB. We propose a way to control the lateral ferromagnetic domain, which is associated with the type of the intermediate state, through the control of the exchange coupling magnitude.