High-Speed Femto-Joule per Bit Silicon-Conductive Oxide Nanocavity Modulator

By combining the large Purcell effect of photonic crystal nanocavity and strong plasma dispersion transparent conductive oxides, ultra-compact silicon modulators with heterogeneously integrated indium-tin-oxide (ITO) can potentially achieve unprecedented energy efficiency. In this article, we report first high-speed modulator driven by an ITO gate, achieving 1.94 GHz bandwidth. On-off-key modulation is measured up to 3 Gb/s only 2 V voltage swing 18.3 fJ/bit addition, perform in-depth analysis efficiency high frequency simulation modulator, revealing critical role played semiconductor conduction path overlapping factor between accumulated free carriers cavity resonant mode. Based on our analysis, propose a strategy further improve bandwidth 23.5 node-matched doping reduce consumption range hundreds atto-joule per bit.