Gate-Tunable Graphene Optical Modulator on Fiber Tip: Design and Demonstration

A fiber-end-face-integrated electrically tunable optical modulator based on graphene field-effect transistor and the fabrication technique are proposed and demonstrated. The all-fiber device features a scheme of compactness and high integration when applied to fiber optical system, as well as a low insertion loss since spatial coupling of light is avoided. A reflecting structure is used and the electro-optic modulator shows vivid modulation when gate voltage gets tuned, with maximum optical reflectance modulation depth over 1% in demonstration. To the best of the authors' knowledge, it is the first time to build an all-solid gate-control modulator directly on fiber facet. The fabrication methods introduce workflows of silicon-on-insulator processing into the optical fiber end-face micromachining domain which can be applied to more comprehensive configurations, broadening the path of fiber-end-face integrated device.

Automated summary

This paper proposes and demonstrates a fiber-end-face-integrated electrically tunable optical modulator based on a graphene field-effect transistor and presents its fabrication methods. The all-fiber device offers compactness, high integration, and low insertion loss, and achieves vivid modulation through a reflecting structure. This is the first time that an all-solid gate-control modulator is directly built on a fiber facet, broadening the development of fiber-end-face integrated devices.