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The lecture entitled "Spin-charge interconversion in 2D van der Waal materials" will be delivered by Dr Safeer Chenattukuzhiyil, a Research Fellow in the Department of Physics at the University of Oxford.

Details

• time: 8.30am
• location: ACMiN, building D-10, room C

Abstract

Graphene has been known as an excellent material for long-distance spin transport due to its weak spin-orbit coupling (SOC). However, the same reason makes graphene an adverse candidate for different spintronics applications in which strong SOC is required, such as the spin-charge interconversion applications. It was predicted theoretically that SOC can be induced in graphene so that spin-orbit phenomena such as spin Hall effect (SHE) or Rashba-Edelstein effect can be obtained. In our work, by using van der Waals heterostructure-based lateral spin valve, we experimentally demonstrated the first unambiguous measurement of spin-to-charge conversion (SCC) due to SHE in graphene via spin-orbit proximity with transition metal dichalcogenides (TMD), MoS2 and WSe2. We extended similar experiments in graphene combined with an insulator, Bi2O3 and CuOx. Then we demonstrated gate tunable SHE in graphene with SCC efficiency larger than in some of the best SCC materials such as topological insulators. Using a similar approach, we performed another set of experiments demonstrating large-efficiency SCC in semi metallic TMDs such as MoTe2, NbSe2, and TaS2. Also, due to the low symmetry crystal structure of these materials, we detect, along with the conventional SCC, unconventional SCCs where the spin polarization, the spin current and the charge current are not mutually orthogonal to each other. In summary, all these different experiments spread light into the understanding of spin-orbit effects in van der Waal materials opening exciting opportunities in a variety of future spintronics and nanomagnetism applications.