Fabrication and Characterization of Edge-Conformed Graphene-Silicon Waveguides

We report a simple and robust method for fabricating graphene-on-silicon waveguides on a silicon-on-insulator (SOI) chip. The waveguide consists of a silicon core covered by a graphene layer whose width exactly conforms with the width of the silicon core and whose length can be precisely controlled. Raman spectroscopy showed that the graphene layer retained its high quality after processing. Transmission measurements of fabricated graphene-on-silicon waveguides showed polarizationdependent propagation losses of 0.03 dB/μm for the transverseelectric (TE) mode and 0.07 dB/μm for the transverse-magnetic (TM) mode, in excellent agreement with theoretical simulations.