Determining Antiferromagnetic Moment Orientations from Domain Images by Pixel-by-Pixel Analysis

Antiferromagnetic (AFM) spintronics has received increased scientific focus for improving power consumption, storage capacity, and processing capabilities of information technology devices. AFM La0.5Sr0.5FeO3 (LSFO) / FM La0.7Sr0.3MnO3 (LSMO) heterostructures are excellent candidates for developing AFM spintronic devices as the AFM moments can be reoriented with applied magnetic fields on the scale of tenths of a tesla utilizing spin-flop coupling, (i.e., perpendicular coupling between ferromagnetic (FM)). In order to understand the AFM and FM domain structure in this heterostructure system, photoemission electron microscopy was performed on LSFO/LSMO heterostructures grown on (001)-oriented (LaAlO3)0.3(Sr2TaAlO6)0.7 substrates. Extended domains are observed parallel to one of the in-plane <100> substrate directions and the FM and AFM moments within each domain display perpendicular orientation as dictated by spin-flop coupling. Pixel-by-pixel analysis was performed on AFM domain images acquired with the E-vector of the linearly polarized x-rays rotating from s- to p-polarization to reveal the population and orientation of the AFM moments.