Deep-Ultraviolet Electro-optic Modulator Based on Fluorographene Liquid Crystal

Graphene-based liquid crystals have ultra-high electric responsivity and hold great promise in fabricating light modulators with ultra-low-field driving and macroscopic centimeter-scale electrode spacing. However, their narrow bandgap and uncontrollable electroresponse severely restrict their modulated spectral region and performance, especially for the visible and ultraviolet regions. Here, we report a fluorographene liquid crystal, which has a wide bandgap of ∼5.5 eV and controllable electroresponse from modulation of fluorine doping ratio, and exceptional stability under deep-ultraviolet exposure. As a consequence, a fluorographene liquid crystal-based deep-ultraviolet electro-optic modulator is fabricated with negligible degradation after 5 h of ultraviolet irradiation under 0 and 12 V m −1 electric fields. The fluorographene liquid crystals expand the family of graphene liquid crystals and pave the way for broadening their applications in a variety of scenarios, as conceptually demonstrated with integrated sea-land-air solar-blind communication for smart port applications.