Voltage Controlled Nanoscale Magnetic Devices for Non-Volatile Memory and Scalable Quantum Computing

Giant magnetoresistance (GMR) and Spin Transfer Torque (STT) are the basis of non-volatile (stores information when powered off) memory known as STTRAM. However, even state-of-the-art extremely scaled magnetic memory devices takes 1000 times more energy to switch compared to today's CMOS devices. This motivates research on electrical field control of magnetization. Electrical field control, for example voltage control of magnetic anisotropy (VCMA) manipulation, of fixed skyrmions can lead to small footprint, energy efficient nanomagnetic memory. We discuss experimental demonstration of VCMA induced nonvolatile creation and annihilation of skyrmions in an antiferromagnet/ferromagnet/oxide heterostructure film followed by simulations to show the feasibility of skyrmion mediated ferromagnetic reversal of perpendicular-Magnetic Tunnel Junctions (MTJs) scaled to less than 20 nm lateral dimensions that can switch in
$\sim \mathbf{20}$
picoseconds. This intermediate skyrmion state provides a pathway for robust magnetization reversal with VCMA without the need for current or a magnetic field. We will also discuss the possibility of tuning the frequency of the skyrmion and nanomagnet oscillations to the Larmor frequency of the spins confined to a nanoscale volume to implement single-qubit quantum gates with fidelities approaching those of fault-tolerant quantum computing. Heterogenous integration and packaging will be key to further development of the above energy efficient computing paradigms.