  This paper discusses the temperature-dependent properties of
(GaIn)As/Ga(AsSb)/(GaIn)As W-quantum well heterostructures for laser
applications based on theoretical modeling as well as experimental findings. A
microscopic theory is applied to discuss band bending effects giving rise to
the characteristic blue shift with increasing charge carrier density observed
in type-II heterostructures. Furthermore, gain spectra for a W-quantum well
heterostructure are calculated up to high charge carrier densities. At these
high charge carrier densities, the interplay between multiple type-II
transitions results in broad and flat gain spectra with a spectral width of
approximately 160 nm. Furthermore, the temperature-dependent properties of
broad-area edge-emitting lasers are analyzed using electroluminescence as well
as laser characteristic measurements. A first indication for the theoretically
predicted broad gain spectra is presented and the interplay between the
temperature-dependent red shift and the charge carrier density-dependent blue
shift is discussed. A combination of these effects results in a significant
reduction of the temperature-induced red shift of the emission wavelengths and
even negative shift rates of (-0.10 plusminus 0.04) nm/K are achieved.
