Heterostructures of 2D materials, such as those formed by stacking monolayers of the semiconductors MoSe2 and WSe2, offer potential new routes to efficient, stable and flexible solar cells. We need to understand and learn to control their electronic and optical properties. In UW Physics we are able to make high quality heterostructures. Xu’s group use optical studies to determine properties such as interlayer exciton diffusion and photocurrent response. Working in David Cobden’s group I will focus on electrical aspects. I will help develop ways to achieve good electrical contacts, for instance by finding how to incorporate noble metal films in the heterostructure stacks, and how to screen depletion regions using gates and chemical doping. I will work on ways to produce large areas of heterojunctions suitable for device arrays, employing the vapor transport growth and chemical exfoliation. I will also work with collaborators to determine the band structure using micro-ARPES.
Advisor: David Cobden