Understanding the anisotropy distribution and mapping the SOT response of compositionally-graded GdCoFe ferrimagnetic alloy films for spint

Recent studies suggest the Dzyaloshinskii-Moriya Interaction (DMI) can be manipulated to stabilize chirality by introducing non-Abstract: uniformity via compositionally-grading in amorphous rare earth (RE): transitional metal (TM) ferrimagnetic thin films. These alloys exhibit magnetization compensation, where the net magnetization or angular momentum vanishes due to competition between opposing RE and TM moments. Near compensation a substantial increase in spin-orbit torque (SOT) efficiency and the occurrence of perpendicular magnetic anisotropy (PMA) have been observed. Critically, it has recently been claimed that the presence of a compositional gradient enables a transition from in-plane to out-of-plane magnetization that is responsible for an observed efficient field-free SOT switching. This experiment will test this notion of anisotropy variation and map the effect of SOT on the spin texture using the magnetic sensitivity of XRMR at the Gd edge in GdCoFe alloys.