Design, fabrication, and characterization of GeSn alloy-based laser sources for mid-infrared silicon photonics

Job description: You will design and fabricate laser and LED sources based on GeSn alloy in a cleanroom environment. These novel group-IV direct-bandgap materials, epitaxially grown on 200 mm Si wafers, are considered CMOS-compatible and hold great promise for the development of low-cost mid-infrared light sources. You will characterize these light sources using a mid-infrared optical test bench, with the goal of their future integration into a Germanium/Silicon photonic platform. Additionally, you will assess the feasibility of gas detection within a concentration range from a few dozen to several thousand ppm. The objectives of the PhD are to: • Design efficient GeSn (Si) stack structures that confine both electrons and holes while providing strong optical gain. • Evaluate the optical gain under optical pumping and electrical injection at different strain levels and doping concentrations. • Design and fabricate laser cavities with strong optical confinement. • Characterize the fabricated devices under optical and electrical injection as a function of their strain state at both room and low temperatures. • Achieve electrically pumped continuous-wave group-IV lasers. • Understand the physical phenomena that may impact the material and device performance for light emission. • Characterize the best-fabricated devices for low-cost environmental gas detection applications. This work will involve collaborations with international laboratories working on the same dynamic research topic.

Your profile: M2 en physique ou en optique / photonique / physique quantique / micro et nanotechnologies.