Researchers from the Max Born Institute in Berlin have made a significant advancement by successfully conducting X-ray Magnetic Circular Dichroism (XMCD) experiments in a laser laboratory for the first time. XMCD is essential for unraveling the magnetic order in nanostructures, which is critical for various technological applications like data storage and sensors. This method exploits the interaction of circularly polarized light with magnetic materials, enabling the precise determination of magnetization in different layers or elements without damaging the samples. Traditionally, such XMCD experiments required large-scale facilities, but this new approach utilizes a laser-driven plasma source, which generates soft X-ray light with a photon energy around 700 eV, suitable for examining iron’s absorption edges.
To overcome the challenge of random polarization from plasma, researchers implemented a magnetic polarization filter that induces the necessary circular polarization. This breakthrough allows for flexible, efficient XMCD spectroscopy in a laboratory setting, providing insights into ultrafast magnetization processes on a picosecond scale. The findings promote the potential of laser-based X-ray sources, offering advantages over conventional methods, and were detailed in the journal OPTICA.
