Van der Waals heterostructures with photo-oxidised high-k dielectrics

Spintronic effects exploit the spin of electrons rather than their charge and could form the basis of a quantum computer. Our technique is closely related to the spin Hall effect. In our case, due to the optically-created polarisation of the charge-carrier spins, a Hall voltage can be measured, in the absence of a magnetic field, on passing a current through the sample.
This offers the intriguing possibility of device potential. Two-dimensional nanomaterials, similar to graphene, also possess a number of bandstructure valleys, opening up the possibility of a valley Hall effect as well as the spin Hall effect.

These nanomaterials also have unique physical properties due to their two-dimensional honeycomb structure of atoms. Strain-engineering is an emerging field in graphene research that exploits that it is only a single atom thick. This makes such two-dimensional nanomaterials amenable to external influences, including mechanical deformation. We will investigate the effect of strain on the Raman and photoluminescence spectra in both supported and suspended devices by exploiting the differential thermal contraction of supported nanomaterials with respect to their substrate and suspended nanomaterials with respect to their contacts.