Optospintronics and Magnetism with 2D Materials and Heterostructures*

I will review our latest developments in spintronics, optospintronics and magnetism in two-dimensional (2D) materials and heterostructures. Graphene continues to exhibit improved properties for spin transport and demonstrates additional functionality through the use of vertically stacked heterostructures. One of the interesting new directions is optospintronics enabled by heterostructures of graphene and transition metal dichalcogenides (TMD). Due to the valley optical selection rules of TMDs and the large spin-orbit coupling, the helicity of the photon is coupled to the valley spin polarization of electrons. Thus, circularly polarized optical excitation into a TMD/graphene heterostructure generates spin polarization in the TMD that subsequently transfers to the graphene. This optical spin injection into graphene is an example of new functionality for the expanding field of 2D spintronics. Also worthy of note within the field is the development of van der Waals magnets in the 2D limit. I will discuss our work along these lines as well as recent efforts to utilize spin-polarized scanning tunneling microscopy for the atomic scale imaging of magnetic order.