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arXiv · 1505.03959

Direct detection of pure spin-current by x-ray pump-probe measurements

J. Li·L. R. Shelford·P. Shafer·A. Tan·J. X. Deng·P. S. Keatley·C. Hwang·E. Arenholz·G. van der Laan·R. J. Hicken·Z. Q. Qiu
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Abstract

By synchronizing a microwave waveform with the synchrotron x-ray pulses, we use the ferromagnetic resonance (FMR) of the Py (Ni81Fe19) layer in a Py/Cu/Cu75Mn25/Cu/Co multilayer to pump a pure spin current into the Cu75Mn25 spacer layer, and then directly probe the spin current in the Cu75Mn25 layer by a time-resolved x-ray magnetic circular dichroism (XMCD). This element-specific pump-probe measurement unambiguously identifies the AC spin current in the Cu75Mn25 layer. In addition, phase resolved x-ray measurements reveal a characteristic bipolar phase behavior of the Co spins that is a fingerprint of spin-current driven spin precession.

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J. Li, L. R. Shelford, P. Shafer, A. Tan, J. X. Deng, P. S. Keatley, C. Hwang, E. Arenholz, G. van der Laan, R. J. Hicken, Z. Q. Qiu. 2016-07-16. Direct detection of pure spin-current by x-ray pump-probe measurements. https://doi.org/10.1103/physrevlett.117.076602

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