Enhancing spin-orbit torque by strong interfacial scattering from ultra-thin insertion layers

Abstract

Increasing dampinglike spin-orbit torque (SOT) is both of fundamental importance for enabling new research into spintronics phenomena and also technologically urgent for advancing low-power spin-torque memory, logic, and oscillator devices. Here, we demonstrate that enhancing interfacial scattering by inserting ultra-thin layers within a spin Hall metals with intrinsic or side-jump mechanisms can significantly enhance the spin Hall ratio. The dampinglike SOT was enhanced by a factor of 2 via sub-monolayer Hf insertion, as evidenced by both harmonic response measurements and current-induced switching of in-plane magnetized magnetic memory devices with the record low critical switching current of ~73 uA (switching current density of 3.6x10^6 A/cm^2). This work demonstrates a very effective strategy for maximizing dampinglike SOT for low-power spin-torque devices.

References in corpus (6)

• Study of Intrinsic Spin Hall Effect and Orbital Hall Effect in 4d- and 5d- Transition Metals
• Spin-orbit torques in heavy metal/ferromagnet bilayers with varying strength of interfacial spin-orbit coupling
• Strong damping-like spin-orbit torque and tunable Dzyaloshinskii-Moriya interaction generated by low-resistivity Pd${}_{1-x}$Pt${}_x$ alloys
• Nanosecond-timescale low error switching of in-plane magnetic tunnel junctions through dynamic Oersted-field assisted spin-Hall effect
• Enhancement of the Anti-Damping Spin Torque Efficacy of Platinum by Interface Modification
• On the origin of field-like spin-orbit torques in heavy metal-ferromagnet-oxide thin film heterostructures

Cited by in corpus (4)

• Benchmarking of spin-orbit torque switching efficiency in Pt alloys
• Energy-efficient ultrafast SOT-MRAMs based on low-resistivity spin Hall metal Au0.25Pt0.75
• Materials Requirements of High-Speed and Low-Power Spin-Orbit-Torque Magnetic Random-Access Memory
• Spin Hall magnetoresistance sensor using Au${}_x$Pt${}_{1-x}$ as the spin-orbit torque biasing layer