  Understanding the carrier dynamics of nanostructures is the key for
development and optimization of novel semiconductor nano-devices. Here, we
study the optical properties and carrier dynamics of (InGa)(AsSb)/GaAs/GaP
quantum dots (QDs) by means of non-resonant energy and temperature modulated
time-resolved photoluminescence. Studying this material system is important in
view of the ongoing implementation of such QDs for nano memory devices. Our set
of structures contains a single QD layer, QDs overgrown by a GaSb capping
layer, and solely a GaAs quantum well, respectively. Theoretical analytical
models allow us to discern the common spectral features around the emission
energy of 1.8 eV related to GaAs quantum well and GaP substrate. We observe
type-I emission from QDs with recombination times between 2 ns and 10 ns,
increasing towards lower energies. The distribution suggests the coexistence of
momentum direct and indirect QD transitions. Moreover, based on the
considerable tunability of the dots depending on Sb incorporation, we suggest
their utilization as quantum photonic sources embedded in complementary
metal-oxide-semiconductor (CMOS) platforms, since GaP is almost lattice-matched
to Si. Finally, our analysis confirms the nature of the pumping power
blue-shift of emission originating from the charged-background induced changes
of the wavefunction topology.
