Element-specific investigation of femtosecond magnetization dynamics
Final Report Abstract
In the framework of the DFG-Project we investigated elementspecific ultrafast magnetization dynamics and domain structure with nm lateral resolution in magnetic thin films, alloys and multilayers employing magneto-optics in the extreme ultraviolet (XUV) and soft X-ray regimes. In the investigations, we were using laser-driven high-harmonic generation (HHG) ultrashort-pulse light as well as synchrotron based sources. Element-specificity and ultrahigh time-resolution of laser driven sources allow access to the magnetic coupling and dynamics on the time-scale of the exchange interaction (≈10-100 fs). Due to experimental constraints, this research area has been largely unexplored, and our work in the framework of the current project contributed substantially to novel insights into both spin dynamics as well as development of experimental methodology. In a systematic manner, we explored the fundamental role of exchange coupling on the ultrafast magnetic response in magnetic materials and looked into previously unexplored field of magnetization dynamics in transition metal (TM) multilayers, TM-TM alloys, as well as Heusler alloys and amorphous rareearth-TM compounds. Access to both M- and L-absorption edges of the magnetic materials at the synchrotron provided the basis to a deeper understanding of the ultrafast magneto-optic response in the XUV spectral range. Our research project addressed element-specific ultrafast magnetization dynamics in complex magnetic materials and multilayers by a unique combination of laboratory based and synchrotron techniques. The defined challenges associated with methodology, materials aspects, and fundamental physics were successfully mastered.
Publications
- Controlling the Competition between Optically Induced Ultrafast Spin-Flip Scattering and Spin Transport in Magnetic Multilayers, Phys. Rev. Lett. 110, 197201 (2013)
E. Turgut, C. La-o-vorakiat, J. M. Shaw, P. Grychtol, H. T. Nembach, D. Rudolf, R. Adam, M. Aeschlimann, C. M. Schneider, T. J. Silva, M. M. Murnane, H. C. Kapteyn & S. Mathias
(See online at https://doi.org/10.1103/PhysRevLett.110.197201) - Femtosecondlaser-induced modifications in Co/Pt multilayers studied with tabletop resonant magnetic scattering, EPL 109, 17001(2015)
C. Weier, R. Adam, D. Rudolf, R. Frömter, P. Grychtol, G. Winkler, A. Kobs, H. P. Oepen, H. C. Kapteyn, M. M. Murnane & C. M. Schneider
(See online at https://doi.org/10.1209/0295-5075/109/17001) - Resonant Magnetic Studies using Synchrotron Radiation and Laser- Generated Extreme Ultraviolet Ligh (= Schriften des Forschungszentrums Jülich Reihe Schlüsseltechnologien / Key Technologies). Forschungszentrum Jülich (2015)
C. Weier
- Employing soft x-ray resonant magnetic scattering to study domain sizes and anisotropy in Co/Pd multilayers, Phys. Rev. B 94, 134413, (2016)
K. Bagschik, R. Frömter, J. Bach, B. Beyersdorff, L. Müller, S. Schleitzer, M. H. Berntsen, C. Weier, R. Adam, J. Viefhaus, C. M. Schneider, G. Grübel, and H.P. Oepen
(See online at https://doi.org/10.1103/PhysRevB.94.134413) - Spatial coherence determination from the Fourier analysis of a resonant soft X-ray magnetic speckle pattern Opt. Express 24, 23162, (2016)
K. Bagschik, R. Frömter, L. Müller, W. Roseker, J. Bach, P. Staeck, C. Thönnißen, S. Schleitzer, M. H. Berntsen, C. Weier, R. Adam, J. Viefhaus, C. M. Schneider, G. Grübel, and H.P. Oepen
(See online at https://doi.org/10.1364/OE.24.023162) - Spin-resolved photoelectron spectroscopy using femtosecond extreme ultraviolet light pulses from highorder harmonic generation, Rev. Sci. Instrum. 87, 043903 (2016)
M. Ploetzing, R. Adam, C. Weier, L. Plucinski, S. Eich, S. Emmerich, M. Rollinger, M. Aeschlimann, S. Mathias & C. M. Schneider
(See online at https://doi.org/10.1063/1.4946782) - Band structure evolution during the ultrafast ferromagnetic-paramagnetic phase transition in cobalt, Science Advances 3 (3), e1602094 (2017)
S. Eich, M. Plötzing, M. Rollinger, S. Emmerich, R. Adam, C. Chen, H. C. Kapteyn, M. M. Murnane, L. Plucinski, D. Steil, B. Stadtmüller, M. Cinchetti, M. Aeschlimann, C. M. Schneider, S. Mathias
(See online at https://doi.org/10.1126/sciadv.1602094)
