Time and Spatially Resolved Hard X-Ray MCD Measurement on a Co/Pt Multilayer Dot Excited by Pulsed RF Field

• Published in: IEEE transactions on magnetics Vol. 54; no. 2; pp. 1 - 6
• Main Authors: Kikuchi, Nobuaki, Osawa, Hitoshi, Suzuki, Motohiro, Kitakami, Osamu
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Cobalt; Dichroism; Electrons; Ferromagnetic resonance; Frequency measurement; Magnetic field measurement; Magnetic moments; Magnetic multilayers; Magnetic resonance; Magnetism; Magnetization; magnetization dynamics; Measurement techniques; Multilayers; Radio frequency; Selectivity; Spatial resolution; spin waves; Synchronism; X-ray magnetic circular dichroism (XMCD)
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2017.2745211

Understanding of magnetization behavior in magnetic nanostructures is a key issue for future magnetic/spintronic devices. Time-resolved X-ray magnetic circular dichroism (XMCD) is a powerful measurement technique with potential of nanometer spatial resolution, picosecond time resolution, and element selectivity. We have carried out time and spatially resolved XMCD microscopy measurement on a Co/Pt multilayer dot by detecting XMCD at the Pt L 3 edge at BL39XU of SPring-8 using hard X-ray. Transient magnetic response of Co/Pt multilayer dots with diameter of 2.6 μm was investigated against pulsed RF field with frequency around 2.5 GHz and the maximum amplitude of about 400 Oe. By synchronizing excitation RF field pulse with X-ray pulses, the growth of magnetization precession of the induced Pt magnetic moment in the dot was clearly observed with sub-100 ps time resolution and submicrometer spatial resolution. The developed measurement setup can be applicable for a wide range of studies for time-resolved hard X-ray experiments.