Alexandr Alekhin, Ilya Razdolski, Nikita Ilin, Jan P. Meyburg, Detlef Diesing, Vladimir Roddatis, Ivan Rungger, Maria Stamenova, Stefano Sanvito, Uwe Bovensiepen, Alexey Melnikov:
Phys. Rev. Lett. 119, 017202 (2017), pp. 6
arXiv:1606.03614 [physics.optics] (2016), pp. 5;
DOI: arXiv:1606.03614 [physics.optics]
Using the sensitivity of optical second harmonic generation to currents, we demonstrate the generation of 250 fs-long spin current pulses in Fe/Au/Fe/MgO(001) pseudo spin valves. The temporal profile of these pulses indicates ballistic transport of hot electron across a sub-100 nm Au layer. The pulse duration is primarily determined by the thermalization time of laser-excited hot carriers in Fe. Considering the calculated spin-dependent Fe/Au interface transmittance we conclude that a non-thermal spin-dependent Seebeck effect is responsible for the generation of ultrashort spin current pulses. The demonstrated rotation of spin polarization of hot electrons upon interaction with non-collinear magnetization at Au/Fe interfaces holds high potential for future spintronic devices.
The original publication is available by link DOI: 10.1103/PhysRevLett.119.017202