Voltage controlled magnetism in Cr₂O₃ based all-thin-film systems

Voltage-control of exchange biases through active selection of distinct domain states of the magnetoelectric and antiferromagnetic pinning layer is demonstrated for Cr₂O₃/CoPd heterostructures. Progress and obstacles towards an isothermal switching of exchange bias are discussed. An alternative approach avoiding exchange bias for voltage-controlled memory exploits boundary magnetization at the surface of Cr₂O₃ as voltage-controlled state variable. We demonstrate readout and switching of boundary magnetization in ultra-thin Cr₂O₃/Pt Hall bar devices where reversal of boundary magnetization is achieved via magnetoelectric annealing with simultaneously applied ±0.5 V and 400 mT electric and magnetic fields.