Advances in large-area graphene synthesis via chemical vapour deposition on metals like copper were instrumental in the demonstration of graphene-based novel, wafer-scale electronic circuits and proof-of-concept applications such as flexible touch panels. Here, we show that graphene grown by chemical vapour deposition on copper is equally promising for spintronics applications. In contrast to natural graphene, our experiments demonstrate that chemically synthesized graphene has a strong spin-orbit coupling as high as 20â ‰meV giving rise to a giant spin Hall effect. The exceptionally large spin Hall angle ∼0.2 provides an important step towards graphene-based spintronics devices within existing complementary metal-oxide-semiconductor technology. Our microscopic model shows that unavoidable residual copper adatom clusters act as local spin-orbit scatterers and, in the resonant scattering limit, induce transverse spin currents with enhanced skew-scattering contribution. Our findings are confirmed independently by introducing metallic adatoms-copper, silver and gold on exfoliated graphene samples.
Bibliographical noteFunding Information:
We thank A. Pachoud, S.X. Lim, J.Y. Tan and I.J. Vera Marun for their help and useful discussions. B.Ö. would like to acknowledge support by the National Research Foundation, Prime Minister’s Office, Singapore under its Competitive Research Programme (CRP Award No. NRF-CRP9-2011-3) and the SMF-NUS Research Horizons Award 2009-Phase II. A.H.C.N. would like to acknowledge support by the National Research Foundation, Prime Minister’s Office, Singapore under its Competitive Research Programme (CRP Award No.NRF-CRP6-2010-5). J.-H.A. acknowledges funding support by the Basic Research Program (2012R1A2A1A03006049 and 2009-0083540) through the National Research Foundation of Korea (NRF), funded by the Ministry of Education, Science and Technology.
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Physics and Astronomy(all)