Atomic Number Dependence of Spin Hall Effect

Abstract

In this thesis, we study the possibility of manipulating electron spins in graphene via spin Hall effect through metallic adatom induction. Here, graphene decorated with gold and silver nanoparticles are used in our model systems. Spin Hall coefficient and spin orbit coupling strength are also extracted and compared. The extracted spin Hall coefficient ~0.1 is in par with the results obtained in heavy metals like platinum. In the second part of the thesis, we study the effect of substrates with large spin orbit coupling strength on graphene. We show that the substrates like tungsten disulfide are able to proximity induce very strong spin orbit interaction, leading to a high non local spin Hall signal. Finally we study the spin Hall effect in locally hydrogenated graphene. While this is shown to not improve the spin relaxation, it opens up the possibility to control the spin orbit coupling locally.