Tri-layer black phosphorus as a light source in Telecom optical wavelength bands

Light sources in telecom bands are crucial for many types of optical communications, such as on-chip, chip-to-chip, rack to rack and fiber communications. However, the common light sources based on III-V group materials have been suffering from integration difficulties. Recently, layered material black phosphorus (BP) has been proved as a direct band gap semiconductor for all different thickness. The emission from BP is not only anisotropic but also thickness dependent. Especially for tri-layer black phosphorus, the emission energy is peaked near 0.86 eV and the broad emission extends to both Telecom E-band and S-band. Limited by the air-sensitive nature, the study related to light emitting devices based on thin layer black phosphorus is still challenging. Here we focus on developing h-BN encapsulated black phosphorus inside glovebox for silicon photonics compatible light sources. The rich electronic and optical properties of BP allow for multiple functionalities and provides new opportunities for integrated optoelectronic systems.