Dresden 2014 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 22: Magnetization Dynamics I
MA 22.11: Vortrag
Mittwoch, 2. April 2014, 12:15–12:30, HSZ 401
Time-resolved MOKE in Au/Fe/MgO(001) structures: hot carrier transport and response of transiently magnetized Au — Alexandr Alekhin1, Damian Bürstel2, Detlef Diesing2, Tim O. Wehling3, Ivan Rungger4, Maria Stamenova4, Stefano Sanvito4, Markus Münzenberg5, Uwe Bovensiepen6, and •Alexey Melnikov1 — 1Fritz-Haber-Institut der MPG, Abt. Phys. Chemie — 2Universität Duisburg-Essen, Institut für Phys. Chemie — 3Universität Bremen, Theor. Phys. Institut — 4Trinity College Dublin, School of Physics and CRANN — 5Universität Göttingen, I. Phys. Institut — 6Universität Duisburg-Essen, Fakultät für Physik
Ultrafast spin dynamics (SD) is the key for development of faster data storage and spintronics devices. In metals with highly mobile hot carriers (HC) SD is essentially non-local and determined by the transport of spin-polarized HC. Therefore we consider the effect of HC transport being superimposed onto SD originating from the spin-lattice interaction. We investigate this non-locality of optically excited SD in Au/Fe/MgO(001) structures observing magneto-optical Kerr effect (MOKE) with 20 fs time resolution. Exciting the Fe layer and probing either the Fe or Au sides of the sample, we demonstrate the crucial role of spin-polarized HC transport in ultrafast SD and reveal a sizable contribution of transiently magnetized Au into the MOKE signal. Finally, we propose a technique for the definition of magneto-optical constants of non-magnetic materials based on spin polarized HC transport and estimate the magneto-optical constant of Au. DFG (ME 3570/1, Sfb 616) and EU 7-th framework program (CRONOS) are acknowledged.