Adaptive Design of Tensile Strained Ge-on-InGaAs QW Laser for MIR Applications

Here, we explore the benefits of an adaptive design (AD) methodology to improve the lasing performance of a ε-Ge-on-InGaAs SCH QW laser. This ε-Ge/InGaAs QW laser structure was analyzed by numerical solvers with aided in-house epitaxial growth and characterization results. The ε-Ge/InGaAs QW exhibited (i) 30% decrease in material loss, (ii) additional net modal gain of 10 cm
^-1
, and (iii) greater than 1 order of magnitude decrease in threshold current density (J
TH
) at indium composition of 24 % by AD methodology. Due to the widespread spectral tunability of the ε-Ge QW laser in the MIR region, the AD approach is essential to ensure efficient performance improvement over standard design methodology with low J
TH
and improved gain for integrated photonics.