Indirect excitation of ultrafast demagnetization
نویسندگان
چکیده
Does the excitation of ultrafast magnetization require direct interaction between the photons of the optical pump pulse and the magnetic layer? Here, we demonstrate unambiguously that this is not the case. For this we have studied the magnetization dynamics of a ferromagnetic cobalt/palladium multilayer capped by an IR-opaque aluminum layer. Upon excitation with an intense femtosecond-short IR laser pulse, the film exhibits the classical ultrafast demagnetization phenomenon although only a negligible number of IR photons penetrate the aluminum layer. In comparison with an uncapped cobalt/palladium reference film, the initial demagnetization of the capped film occurs with a delayed onset and at a slower rate. Both observations are qualitatively in line with energy transport from the aluminum layer into the underlying magnetic film by the excited, hot electrons of the aluminum film. Our data thus confirm recent theoretical predictions.
منابع مشابه
Superdiffusive Spin Transport and Ultrafast Magnetization Dynamics Femtosecond spin transport as the route to ultrafast spintronics
Battiato, M. 2013. Superdiffusive Spin Transport and Ultrafast Magnetization Dynamics: Femtosecond spin transport as the route to ultrafast spintronics. Acta Universitatis Upsaliensis. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1061. 62 pp. Uppsala. ISBN 978-91-554-8722-5. The debate over the origin of the ultrafast demagnetization has be...
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