Photonic technologies have become ubiquitous in our modern society: infrared photodetectors and modulators enable optical communications and the internet, compact cameras in mobile devices make the instantaneous recording of precious moments possible, and solar cells provide environmentally-friendly electricity. Traditional photonics technologies often use a specific material to cover a particular wavelength range, with integration of multiple types 0f photonic materials to cover a broader range highly challenging. This EFRI team will investigate fundamental optical sciences and explore practical photonic applications of a novel two-dimensional (2D) material, black phosphorus (BP), which can cover a broad wavelength range from visible to mid-infrared and can be easily integrated with other photonic platforms due to its layered structure. The team will develop approaches for large-scale black phosphorus synthesis, material characterization, and BP device realization and testing, thus establishing the foundation for black phosphorus based photonic technologies. This project will transform many technological areas relying on optical imaging, sensing and communications, contributing to the National Photonics Initiative (NPI). The team consists of five investigators from four universities (Yale University, Massachusetts Institute of Technology, University of Southern California, and Washington University in St. Louis) and covers multiple disciplines including material sciences, physics, and engineering. This EFRI program will also provide students at different levels, especially those from underrepresented groups, and postdocs with multidisciplinary research experience fostered by the EFRI team, as well as through interactions with the industrial and international partners.
This project will leverage recently rediscovered 2D layered black phosphorus to develop novel photonic devices for optical communications and infrared imaging, while exploring its integration with other 2D (e.g. graphene) and bulk (e.g. silicon) materials. In particular, the team will utilize BP?s widely tunable bandgap with layer number and its robust, anisotropic excitons to explore new optical sciences and to transform present photonic technologies. Establishing the theory, synthesis, encapsulation, and characterization approaches of few-layer and thin-film BP, as well as the fabrication and benchmarking of BP photonic device performance will build the foundation of this paradigm shift in photonic devices. Scientifically, exploration of anisotropic excitons and their tunability by electric field in few-layer BP will advance our basic understanding of many body physics in materials with low crystalline symmetry. Technologically, high carrier mobility, direct bandgap and strong light-BP interaction will enable the realization of a number of high performance BP photonics devices especially in strategically critical near- and mid-infrared wavelength range.
