Graphene-based optical modulators

Optical modulators (OMs) are a key device in modern optical systems. Due to its unique optical properties, graphene has been recently utilized in the fabrication of optical modulators, which promise high performance such as broadband response, high modulation speed, and high modulation depth. In this paper, the latest experimental and theoretical demonstrations of graphene optical modulators (GOMs) with different structures and functions are reviewed. Particularly, the principles of electro-optical and all-optical modulators are illustrated. Additionally, the limitation of GOMs and possible methods to improve performance and practicability are discussed. At last, graphene terahertz modulators (GTMs) are introduced.