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arXiv · 1511.09060

Ultrafast electron-phonon-magnon interactions at noble metal-ferromagnet interfaces

V. Shalagatskyi·O. Kovalenko·V. Shumylo·A. Alekhin·G. Vaudel·T. Pezeril·V. S. Vlasov·A. M. Lomonosov·V. E. Gusev·D. Makarov·V. V. Temnov
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Abstract

Ultrafast optical excitation of gold-cobalt bilayers triggers the nontrivial interplay between the electronic, acoustic, and magnetic degrees of freedom. Laser-heated electrons generated at the gold-air interface diffuse through the layer of gold and strongly overheat the lattice in cobalt resulting in the emission of ultrashort acoustic pulses and generation of exchange-coupled magnons. Time-resolved optical measurements allow for extracting the thermal boundary (Kapitza) resistances at metal/metal interfaces and the hot electron diffusion length in ferromagnetic materials. Both the experimental data and the analytical treatment of the two-temperature model reveal the role of the Kapitza resistance in transient lattice overheating.

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V. Shalagatskyi, O. Kovalenko, V. Shumylo, A. Alekhin, G. Vaudel, T. Pezeril, V. S. Vlasov, A. M. Lomonosov, V. E. Gusev, D. Makarov, V. V. Temnov. 2017-07-27. Ultrafast electron-phonon-magnon interactions at noble metal-ferromagnet interfaces. https://arxiv.org/abs/1511.09060

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