München 2019 – wissenschaftliches Programm
K 2.5: Vortrag
Dienstag, 19. März 2019, 12:20–12:40, HS 3
Imaging of ultrafst demagnetization using high-harmonic radiation — •Sergey Zayko1, Ofer Kfir1, Michael Heigl2, Michael Lohmann1, Murat Sivis1, Manfred Albrecht2, and Claus Ropers1 — 1IV. Physical Institute - Solids and Nanostructures , University of Göttingen — 2Experimental Physics IV, Institute of Physics, University of Augsburg
Laser-driven sources of extreme-UV radiation based on high-harmonic generation (HHG) provide unique access to femtosecond-to-attosecond pulses, and thus, become an indispencible tool for ultrafast dynamics studies. However, the combination of these temporal properties with real-space imaging  remained challenging. Here, we report on the first demonstration of nanoscale imaging of ultrafast dynamics using HHG source. Using a synergy of holography and coherent diffractive imaging we quantitatively map the magnetization state of worm-like domains as they undergo femtosecond demagnetization. This versatile element-specific dynamical microscope allows for comprehensive studies of ultrafast magnetism  in space and time, compatible with a wide-range in-situ control, e.g., with external magnetic and electric fields, currents, light and temperature.
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