Multiangle Reconstruction of Domain Morphology with All-Optical Diamond Magnetometry

Scanning diamond magnetometers based on the optically detected magnetic resonance of the nitrogenvacancy center offer very high sensitivity and noninvasive imaging capabilities when the stray fields emanating from ultrathin magnetic materials are sufficiently low (less than 10 mT). Beyond this low-field regime, the optical signal quenches and a quantitative measurement is challenging. While the fielddependent photoluminescence from the nitrogen-vacancy center can still provide qualitative information on magnetic morphology, this operation regime remains unexplored, particularly for surface magnetization larger than approximately 3 mA. Here, we introduce a multiangle reconstruction (MARE) that captures the full nanoscale domain morphology in all magnetic field regimes leading to photoluminescence quench. To demonstrate this, we use [Ir/Co/Pt]14 multilayer films with surface magnetization an order of magnitude larger than previous reports. Our approach brings noninvasive nanoscale magnetic field imaging capability of the nitrogen-vacancy center to the study of a wider pool of magnetic materials and phenomena.