A performance comparison of ITO and graphene-based electro-optic modulators

Electro-optic modulators (EOMs) are used to change the amplitude and/or phase of the incident light beam by altering the optical properties of a material with an applied voltage. Even though silicon-based EOMs have been demonstrated experimentally, future chip-based optical communication and signal processing technologies require EOMs with a high modulation depth, compact footprint, large bandwidth, low power consumption and cost. In this direction, indium tin oxide (ITO) and graphene have attracted significant attention primarily due to their extraordinary electro-optic properties for the design of such highperformance EOMs.