Gain and Threshold Improvements of 1300 nm Lasers based on InGaAs/InAlGaAs Superlattice Active Regions

Andrey Babichev; Evgeniy Pirogov; Maksim Sobolev; Sergey Blokhin; Yuri Shernyakov; Mikhail Maximov; Andrey Lutetskiy; Nikita Pikhtin; Leonid Karachinsky; Innokenty Novikov; Anton Egorov; Si-Cong Tian; Dieter Bimberg

doi:10.1109/JQE.2025.3553022

paper

Gain and Threshold Improvements of 1300 nm Lasers based on InGaAs/InAlGaAs Superlattice Active Regions

arXiv:2408.02469 · doi:10.1109/JQE.2025.3553022

Abstract

A detailed experimental analysis of the impact of active region design on the performance of 1300 nm lasers based on InGaAs/InAlGaAs superlattices is presented. Three different types of superlattice active regions and waveguide layer compositions were grown. Using a superlattice allows to downshift the energy position of the miniband, as compared to thin InGaAs quantum wells, having the same composition, being beneficial for high-temperature operation. Very low internal loss (~6 $c m^{- 1}$ ), low transparency current density of ~500 $A / c m^{2}$ , together with 46 $c m^{- 1}$ modal gain and 53 % internal efficiency were observed for broad-area lasers with an active region based on a highly strained $I n_{0.74} G a_{0.26} A s / I n_{0.53} A l_{0.25} G a_{0.22} A s$ superlattice. Characteristic temperatures $T_{0}$ and $T_{1}$ were improved up to 76 K and 100 K, respectively. These data suggest that such superlattices have also the potential to much improve VCSEL properties at this wavelength.