Dynamic X-ray magnetic circular dichroism of yttrium iron garnet

High-brilliance X-rays with a broad energy range, provided by synchrotron facilities, have played a crucial role in revealing the electronic, magnetic, and lattice properties of condensed matter systems. Recently, the pulsed nature of synchrotron X-rays has enabled a variety of time-resolved experiments. In this study, we employed a time-resolved XFMR (X-ray Ferromagnetic Resonance) technique to measure the dynamic XMCD (X-ray Magnetic Circular Dichroism) spectrum of Yttrium Iron Garnet by probing the precessional motion of magnetization. The dynamic XMCD spectrum, obtained by sweeping the X-ray photon energy under the optimal XFMR condition, provides information comparable to that of static XMCD. Due to the fluorescence-based detection scheme of XFMR, the L 2 peak appears with high clarity, and the baseline remains flat and artifact-free, demonstrating the potential of dynamic XMCD as a powerful alternative to conventional XMCD techniques. • Developed a time-resolved X-ray ferromagnetic resonance technique to measure ferromagnetic resonance using tens of picosecond X-ray pulses. • Measured the dynamic X-ray magnetic circular dichroism spectrum of the yttrium iron garnet using the fluorescent X-ray ferromagnetic resonance technique. • Developed a method to measure an X-ray magnetic circular dichroism spectrum without modulation of the polarizations of magnetic field or X-ray.