Strained GeSn-on-insulator quantum well laser for the extended-NIR silicon photonics (Conference Presentation)

Group IV materials suffers from a lack of efficient light generation for the on-chip integration of active photonic component on silicon (Si). One of the solutions is to use new material like Germanium-tin alloys (GeSn) that can provide direct band gap alignment of the band structure. The use quantum well (QW) is known, in principle, to favor room temperature laser operation at reasonable thresholds over bulk material. While most of advances were performed with bulk materials, exploring adequate designs of GeSn/SiGeSn based QW including strain engineering should be helpful for futures developments of Si-based active photonic devices. Here we demonstrate up to 290 K laser operation in GeSn/GeSn multi-QW microdisks cavities under optical pumping. The QW and barrier were performed by varying the Sn content. We used specific layer transfer technology and a Silicon Nitride (SiN) stressor layer was introduced to inject tensile strain in the active region such to enhance the directness of the transition. Interestingly this is the highest temperature of operation for GeSn quantum wells lasers. This progress opens the route towards room temperature electrically pumped laser operating.