2D-material-enabled multifunctional mid-IR optoelectronics

New narrow-gap two-dimensional (2-D) semiconductors exemplified by black phosphorus and tellurene are promising material candidates for mid-IR optoelectronic devices. In particular, tellurene, atomically thin crystals of elemental tellurium, is an emerging narrow-gap 2-D semiconductor amenable to scalable solution-based synthesis and large-area deposition. It uniquely combines tunable bandgap energies, high carrier mobility, exceptionally large electro-optic activity, and superior chemical stability, making it a promising and versatile material platform for mid-infrared photonics. Here we discuss the design and experimental realization of integrated photonic devices based on tellurene and other 2-D semiconductors specifically for the mid-IR spectral regime based on a chalcogenide glass (ChG) photonic platform.