  We investigate spatially resolved variations in the bandgap energy across
multiple InxGa1-xAs quantum wells (QWs) on a GaAs substrate within a
metamorphic laser structure. Using high resolution scanning transmission
electron microscopy and low-loss electron energy loss spectroscopy, we present
a detailed analysis of the local bandgap energy, indium concentration, and
strain distribution within the QWs. Our findings reveal significant
inhomogeneities, particularly near the interfaces, in both the strain and
indium content, and a bandgap variability across QWs. These results are
correlated with density functional theory simulations to further elucidate the
interplay between strain, composition, and bandgap energy. This work
underscores the importance of spatially resolved analysis in understanding, and
optimising, the electronic and optical properties of semiconductor devices. The
study suggests that the collective impact of individual QWs might affect the
emission and performance of the final device, providing insights for the design
of next-generation metamorphic lasers with multiple QWs as the active region.
