Proceedings Article | 11 October 2017
KEYWORDS: Absorption, Nanostructures, Control systems, Metals, Diffusion, Applied physics, Nanotechnology, Magnetism
Manipulation of spin accumulation has shown to be a versatile tool for both fundamental research and functional application since it enables to study spin injection and transport in non-magnetic materials, as well as spincaloritronics, spin-orbitronics effects and spin transfer torque [1].
In this presentation, we shows how spin accumulation can be engineered, and what functional behaviors can be obtain through spin accumulation control:
By manipulating spin accumulation in a lateral device through precession or absorption [2, 3], it is possible to extract independently transport parameters of a ferromagnetic material or of a heavy metal with strong spin orbit interaction. Anisotropic absorption in a ferromagnetic element notably enables to obtain both its spin diffusion length and its spin precession length.
Lateral devices are an adapted tool to manipulate spin accumulation for functional application thanks to the high flexibility of their geometry. Nevertheless, lateral devices had always been confined to fundamental research due to the smallness of the signal they emit. We briefly show that lateral devices can emit signal comparable to what is obtain from CPP geometry, as giant magnetoresistance exceeding 10% in an downscaled CoFe-based lateral spin valve [4,5]. We then highlight that the use of lateral devices enables many applicable functions as enhancing spin signal amplitudes, or engineering simultaneously several spin accumulation degrees of freedom. Finally, using a confined spin accumulation located between two tunnel barriers, we show that it is possible to observe a novel magnetoresistive effect that only requires one ferromagnetic element.
[1] Y. Otani et al., Phil. Trans. of the Royal Society of London A 369, 3136 (2011)
[2] F. J. Jedema, et al., Appl. Phys. Lett. 81, 5162 (2002)
[3] M. Isasa et al., Physical Review B 91, 2 (2015)
[4] Y. K. Takahashi, et al. Applied Physics Letters 100, 5 (2012)
[5] G. Zahnd, et al., IOP. Nanotechnology 27, 3 (2015).
