Integrated waveguide assisted electron emission device

Abstract

We introduce the novel approach along with the experimental demonstration of enhanced photon assisted electron emission from monolayer graphene sheet placed over an optical waveguide. A critical challenge on state of the art photon assisted electron emission is low quantum efficiency (QE). One technique that improves QE is enhancing the optical absorption of the incident laser. Here, we specifically introduce utilizing integrated photonic waveguide under electron emitter layer as a mean to transport the photons and evanescently couple them to emitter layer. This evanescent coupling occurs through longer interaction length and photons can be absorbed efficiently compared to free space laser illumination from top on a monolayer of graphene. We also measured the free space photon assisted electron emission from graphene sheet and compared with the performance of the integrated photon assisted emission device.