Presented by Bowei Zhou, Physics Graduate Student
When
2 – 3 p.m., March 1, 2024
Where
Abstract: Magnetic random-access memory ( MRAM) is poised to be a mainstream nonvolatile memory for many advanced applications. Conventional MRAMs are based on magnetic tunnel junctions (MTJs) with ferromagnetic (FM) storage layers, where the memory cells can be switched by the spin transfer torque (STT) effect in the time scale of a few nanoseconds. It has been predicted that MTJs with ferrimagnetic (Ferri) storage layers can operate much faster. Here we developed a new Ferri-MTJs with multilayered composite ferrimagnetic storage layers where both a large tunneling magnetoresistance (TMR) and a high switching speed can be simultaneously achieved. Due to the staggered magnetizations of ferrimagnets, the interaction of spin currents with local moments can extend to a much larger thickness than ferromagnets. This feature is important for small MTJs at sub-10nm scale.