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Room-temperature yellow-orange (In,Ga,Al)P–GaP laser diodes grown on (n11) GaAs substrates
We report room temperature injection lasing in the yellow–orange
spectral range (599–605 nm) in (AlxGa1–x)0.5In0.5P–GaAs diodes with 4 layers of tensilestrained
InyGa1–yP quantum dot-like insertions. The wafers were grown by metal–organic
vapor phase epitaxy side-by-side on (811), (211) and (322) GaAs substrates tilted towards the
<111> direction with respect to the (100) surface. Four sheets of GaP-rich quantum barrier
insertions were applied to suppress leakage of non-equilibrium electrons from the gain
medium. Laser diodes having a threshold current densities of ~7–10 kA/cm2 at room
temperature were realized for both (211) and (322) surface orientations at cavity lengths of
~1mm. Emission wavelength at room temperature ~600 nm is shorter by ~8 nm than
previously reported. As an opposite example, the devices grown on (811) GaAs substrates did
not show lasing at room temperature.