Researchers from Korea's Ulsan National Institute of Science & Technology (UNIST) have designed a new MRAM structure, based on graphene, that offers higher efficiency (and lower heat generation) compared to existing MRAM solutions.
The design of the MRAM device is based on a graphene layer sandwiched between a magnetic insulator (yttrium iron garnet) and a ferroelectric material (PVDF-TrFE). Upon application of a voltage pulse, the current flow through the graphene is altered, enabling the storage of binary data based on this current direction.
The research employs advanced physics concepts, including the inverse Edelstein effect and ferromagnetic resonance (FMR). The spin current injected into graphene via the magnetic insulator's ferromagnetic resonance converts into charge current through the inverse Edelstein effect. By applying a voltage pulse to the ferroelectric, the Fermi level of the graphene shifts, thus modifying the current direction.
