Correlation between the magnitude of interlayer exchange coupling and charge-to-spin conversion efficiency in a synthetic antiferromagnetic system

Abstract

The correlation between the magnitude of interlayer exchange coupling (J ex) and charge-to-spin conversion efficiency (spin Hall angle: θ SH) is investigated in a synthetic antiferromagnetic (AF) system with compensated magnetization. The magnitude of θ SH increases linearly with increasing the magnitude of J ex. We observe the factor of 6.5 increase of spin Hall angle (θ SH = 45.8%) in a low resistive (ρ xx = 41 μΩcm) synthetic AF system by increasing the magnitude of J ex. The low resistive synthetic AF system will be a promising building block for future nonvolatile high-speed memories and logic circuits using the spin Hall effect.