2020/05/17 by Thierry Ruchon, Ruchon, Thierry, Mauro Fanciulli +1
Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #FOS: Physical sciences #Magnetic properties of thin films #Magneto-Optical Properties and Applications #Optics (physics.optics) #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.2005.08349
openalex publication_date 2020/05/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Identifying and imaging spin textures of ever more complex magnetic structures has become a major challenge in the past decade, especially at ultrashort timescales. Most of current approaches are based on the analysis of their polarization and magnetization-dependent reflectivities. Based on our joint publication XXX XX XXXXXX, we introduce a different concept, centered on the coupling of magnetic structures with light beams carrying orbital angular momentum (OAM). Upon reflection by a magnetic vortex, an incoming beam with a unique value ℓ of OAM gets enriched in the neighboring OAM modes ℓ± 1. It results in anisotropic far-field images, which are identified as a Magnetic Helicoidal Dichroism (MHD) signal. Their analysis allow to retrieve the complex magneto-optical constants with excellent precision. This method, which does not require any polarization-resolved analysis, is promising for a quick identification of spin textures, including with attosecond to femtosecond time resolutions.