The talk will address recent experimental progress in this field of 2D-spintronics. I will start with an overview of the experimental state-of-the-art and describe our understanding of the possible spin relaxation mechanisms in graphene, which are the key to achieve full control of the spin degree of freedom. I will show how the dominant relaxation process can be identified by measuring the anisotropy of the spin relaxation with oblique Hanle experiments [2]. This technique also provides valuable information on spin-orbit proximity effects, which are particularly strong in graphene/TMDC heterostructures : the spin-valley coupling of WS2 and MoS2 can be imprinted to graphene, leading to strong spin filtering effects and enabling new strategies for spin manipulation [3].

The second part of the talk will be devoted to the charge-to-spin conversion at the surface of topological insulators (Edelstein effect). The controlled fabrication of TIs by molecular beam epitaxy will be discussed, and I will show how material and interface engineering provides control on the electronic structure of these small band gap semiconductors [4]. I will then present systematic measurements of the non-equilibrium spin-orbit torques in TI/ferromagnet bilayers by current-induced ferromagnetic resonance, and show experimental evidence for a large Edelstein effect at room temperature.

[1] D. Pesin and A. H. MacDonald, Nature Mater. 11, 409 (2012) ; X. Xu et al., Nature Phys. 10, 343 (2014) ; S. Roche et al., 2D Mater 2, 030202 (2015) ;

[2] B. Raes et al., Nature Commun. 7, 11444 (2016) ; B. Raes et al., Phys. Rev. B 95, 085403 (2017).

[3] L. A. Benítez et al., Nature Phys. (accepted).

[4] F. Bonell et al., Cryst. Growth Des. 17, 4655 (2017).

Contact : olivier.boulle@cea.fr