Advancing Characterization for Magnetic Materials via Magneto‐Optical Kerr Effect Microscopy

Abstract The magneto‐optical Kerr effect (MOKE) microscopy is a powerful tool for characterizing magnetic materials, leveraging its high surface sensitivity, nondestructive nature, rapid scanning capability, and real‐time imaging functionality. This technique probes surface magnetization states by detecting polarization rotation or intensity variations in reflected polarized light, with three distinct operational modes (polar, longitudinal, transverse) tailored to different magnetization orientations. MOKE applications span diverse magnetic material systems, including metals and alloys, complex oxides, and polymer nanocomposites. This review comprehensively surveys MOKE developments, encompassing fundamental principles, operational modalities, comparative advantages over conventional magnetic characterization techniques, applications across material classes, and recent advancements—such as MOKE for high‐resolution spectroscopy of 2D materials and topological magnetic structures.