Ultra-compact hybrid silicon:chalcogenide waveguide temperature sensor.

We demonstrate a real-time, reusable, and reversible integrated optical sensor for temperature monitoring within harsh environments. The sensor architecture combines the phase change property of chalcogenide glasses (ChG) with the high-density integration advantages of high index silicon waveguides. To demonstrate sensor feasibility, ChG composition GeS, which is characterized by a sharp phase transition from amorphous to crystalline phase around 415 °C, is deposited over a 50 µm section of a single mode optical waveguide.