Unipolar electric-field-controlled nonvolatile multistate magnetic memory in FeRh/(001)PMN-PT heterostructures over a broad temperature span

Multistate magnetic memory effect in heterostructures composed of FeRh thin films with antiferromagnetic (AFM)-ferromagnetic (FM) phase transition and (001)-oriented PMN-PT substrates has been investigated. Utilizing a unipolar electric field, the nonvolatile change in magnetization was nearly doubled compared with that obtained utilizing a conventional bipolar bias. Four stable nonvolatile magnetic states were obtained over a broad temperature span, from 320 to 390 K, by adjusting the amplitude of the unipolar electric pulses, demonstrating the possibility of realizing a multistate nonvolatile magnetic memory in the FeRh/PMN-PT heterostructures. This work provides a new strategy for enhancing the magnetic response by utilizing unipolar electric fields and promotes the utilization of AFM-FM phase transition materials in multifunctional information storage and novel spintronic devices.