You are here : Home > The Sinaps team > Lasing effect and optical gain simulation in Germanium-Tin (GeSn) micro-cavities

agenda


PhD defense

Lasing effect and optical gain simulation in Germanium-Tin (GeSn) micro-cavities

Wednesday, October 16, 2019 at 2:00 p.m., Chrome 1 room of the Maison Minatec, 3 Parvis Louis Néel, Grenoble
Published on 16 October 2019

​By Quang Thai
Silicon Nanoelectronics Photonics and Structures Team (SiNaPS)

This PhD thesis deals with the study of lasing effect in GeSn layers, with the concentration of Sn positioned between 13% and 16%. First, I analyze their photoluminescence - taking into account the effect of the concentration of Sn, of the applied strain and of the temperature – using a FTIR spectrometer. Lasing effect in GeSn micro-cavities is then characterized using the similar experimental setup, revealing the effect of the concentration of Sn and the density of defects on the lasing temperature and the lasing threshold. These observations are then further studied with simulations of optical gain and lasing characteristics. The results suggest that limiting the effect of intervalence absorption and increasing the non-radiative lifetime should be considered in order to achieve a performant GeSn laser at room temperature. These remarks drive the attention towards uniaxial [100] and biaxial (100) strained GeSn layers, with the last chapter dedicated to explore their evolution of the direct and indirect gaps using a tight-binding approach.