SOC sample
Schematic representation of a WSe2/graphene/hBN heterostructure indicating the opposite spin-orbit field in the K and K’ valley. A typical weak antilocalization curve is shown in the back.

One of the key properties of graphene for spintronics is its capability to transport spins over long distances unaltered. However, the need to manipulate the spins for information processing and storage is also of fundamental importance. The two dimensional heterostructure composed of tungsten diselenide and graphene allows manipulating the spins while preserving graphene’s exceptional electron properties. Using weak antilocalization measurements, the authors find an anisotropic spin lifetime with out-of-plane spins living much longer than in-plane spins. This originates from a special spin-orbit coupling that leads to a Zeeman field that has opposite sign in the two valleys K and K’.

“Large spin relaxation anisotropy and valley-Zeeman spin-orbit coupling in WSe2/Gr/hBN heterostructures”
S. Zihlmann, A. W. Cummings, J. H. Garcia, M. Kedves, K.Watanabe, T. Taniguchi, C. Schönenberger and P. Makk
Physical Review B 97, 075434 (2018)
https://arxiv.org/abs/1712.05678

 

Paper on proximity induced spin-orbit coupling in graphene appeared