Breaking the current density threshold in spin-orbit-torque magnetic random access memory

Abstract

Spin-orbit-torque magnetic random access memory (SOT-MRAM) is a promising technology for the next generation of data storage devices. The main bottleneck of this technology is the high reversal current density threshold. This outstanding problem of SOT-MRAM is now solved by using a current density of constant magnitude and varying flow direction that reduces the reversal current density threshold by a factor of more than the Gilbert damping coefficient. The Euler-Lagrange equation for the fastest magnetization reversal path and the optimal current pulse are derived for an arbitrary magnetic cell. The theoretical limit of minimal reversal current density and current density for a GHz switching rate of the new reversal strategy for CoFeB/Ta SOT-MRAMs are respectively of the order of $10^5$ A/cm${}^2$ and $10^6$ A/cm${}^2$ far below $10^7$ A/cm${}^2$ and $10^8$ A/cm${}^2$ in the conventional strategy. Furthermore, no external magnetic field is needed for a deterministic reversal in the new strategy.

References in corpus (17)

• Spin torque switching with the giant spin Hall effect of tantalum
• Spin Hall effect
• Current-driven Magnetization Reversal and Spin Wave Excitations in Co/Cu/Co Pillars
• Current-driven dynamics of chiral ferromagnetic domain walls
• Symmetry and magnitude of spin-orbit torques in ferromagnetic heterostructures
• Magnetization switching by spin-orbit torque in an antiferromagnet/ferromagnet bilayer system
• Control of spin-orbit torques through crystal symmetry in WTe2/ferromagnet bilayers
• Thermally assisted magnetization reversal in the presence of a spin-transfer torque
• Field-free magnetization reversal by spin-Hall effect and exchange bias
• Threshold current for switching of a perpendicular magnetic layer induced by spin Hall effect
• Observation of Spin-Orbit Effects with Spin Rotation Symmetry
• Magnetization reversal through synchronization with a microwave
• Theoretical limit of the minimal magnetization switching field and the optimal field pulse for Stoner particles
• Critical current under an optimal time-dependent polarization direction for Stoner particles in spin-transfer torque induced fast magnetization reversal
• Electrical control over perpendicular magnetization switching driven by spin-orbit torques
• Efficient Magnetization Reversal with Noisy Currents
• Euler equation of the optimal trajectory for the fastest magnetization reversal of nano-magnetic structures

Cited by in corpus (8)

• Current-Driven Dynamics of Magnetic Hopfions
• Intrinsic Spin Hall Conductivity of MoTe2 and WTe2 Semimetals
• Unconventional magnon excitation by off-resonant microwaves
• Subnanosecond magnetization reversal of magnetic nanoparticle driven by chirp microwave field pulse
• Optimal protocol for spin-orbit torque switching of a perpendicular nanomagnet
• Anomalies in the switching dynamics of C-type antiferromagnets and antiferromagnetic nanowires
• Intrinsic Picosecond Magnetic Switching Mechanism Assisted by an Electric Field in a Synthetic Antiferromagnetic Structure
• Anomalous spin Hall and inverse spin Hall effects in magnetic systems