Graphene-Based Optical Modulator: A Pioneering Demonstration in 2011

In 2011, Liu et al. from the University of California at Berkeley presented the inaugural demonstration of a prototype modulator device. The device utilized a graphene sheet grown through chemical vapor deposition (CVD), which was mechanically transferred onto a silicon-on-insulator (SOI) waveguide. A counter electrode was subsequently deposited atop the graphene layer to facilitate the application of electrical gating on the graphene sheet.