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arXiv · 1803.03090

Competing spin transfer and dissipation at Co/Cu(001) interfaces on femtosecond timescales

J. Chen·U. Bovensiepen·A. Eschenlohr·T. Müller·P. Elliott·E. K. U. Gross·J. K. Dewhurst·S. Sharma
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Abstract

By combining interface-sensitive non-linear magneto-optical experiments with femtosecond time resolution and ab-initio time-dependent density functional theory, we show that optically excited spin dynamics at Co/Cu(001) interfaces proceeds via spin-dependent charge transfer and backtransfer between Co and Cu. This ultrafast spin transfer competes with dissipation of spin angular momentum mediated by spin-orbit coupling already on sub 100 fs timescales. We thereby identify the fundamental microscopic processes during laser-induced spin transfer at a model interface for technologically relevant ferromagnetic heterostructures.

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J. Chen, U. Bovensiepen, A. Eschenlohr, T. Müller, P. Elliott, E. K. U. Gross, J. K. Dewhurst, S. Sharma. 2018-11-29. Competing spin transfer and dissipation at Co/Cu(001) interfaces on femtosecond timescales. https://doi.org/10.1103/physrevlett.122.067202

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