Spin-orbit torques and magnetization switching in perpendicularly magnetized epitaxial Pd/Co2FeAl/MgO structures

Epitaxial magnetic heterostructures of MgO(001)//Pd/Co2FeAl/MgO are grown by magnetron sputtering and the current-induced spin-orbit torques are quantified using harmonic Hall measurements. We demonstrate efficient current-induced spin-orbit-torque switching in perpendicularly magnetized samples. The advantage of such heterostructures for spin-orbit-torque magnetic random-access memory devices is that they allow a combination of critical ingredients: (i) the low resistivity required for reduced electric energy consumption during writing, (ii) the compatibility with a high tunnel magnetoresistive ratio required for efficient reading, and (iii) strong perpendicular magnetic anisotropy for increased thermal stability.