The Japan Society of Applied Physics

2023 International Conference on Solid State Devices and Materials

2023 International Conference on Solid State Devices and Materials

2023年9月5日 〜 2023年10月31日
Nagoya Congress Center

11:30 〜 11:45

[H-6-04] A Novel Tensile Strained Ge/InGaAs Quantum Well Laser for MIR Applications

○Rutwik Joshi1, Steven Johnston2, Sengunthar Karthikeyan1, Mantu Hudait1 (1. Virginia Tech, (United States of America), 2. National Renewable Energy Lab. (United States of America))

https://doi.org/10.7567/SSDM.2023.H-6-04

A tensile strained Ge/InGaAs quantum well (QW) laser is proposed and evaluated using in-house materials growth and characterization results feeding to TCAD solvers. This e-Ge/InGaAs laser provides type-I band alignment with high valence band and conduction band offsets, along with high minority carrier lifetime. At indium (In) = 28% in InGaAs, the e-Ge active layer is a direct-gap material due to the tensile strain and lasing is possible at a wavelength of ~ 2.1 µm with a threshold current density ~ 6 kA/cm2, an improvement over existing Ge lasers and comparable to direct gap MIR lasers. The high band offsets and carrier lifetime enable this e-Ge QW laser to provide a high net material gain of 1211 cm-1 with an improved efficiency of 20 %.