Discover the material scientists using graphene to deliver fiber optics to hard-to-reach communities.
Currently, the modulation of light used in telecom transmissions requires costly and relatively large electro-optic modulators (EOMs). These devices operate at high voltages and require special care to track and adjust their power. Made with expensive non-linear crystals, EOMs are only compatible in a fiber optic geometry, and they do not manage reflection, only transmission.
UW-Madison researchers Victor Brar and Seyoon Kim have developed a new method for controlling the intensity of monochromatic light using electric signals. The team created a tunable dielectric resonator that uses graphene and an electrostatic gate to modulate absorption rates at the qBIC resonant frequency. Strongly gated graphene results in near perfect reflectivity at telecom frequencies. Ungated, it becomes highly transmissive with zero reflection. This results in a compact device that operates at very high speeds.