Epitaxial growth of GaInAs/AlGaAsSb quantum cascade lasers

Molecular beam epitaxial growth of quaternary barrier GaInAs/AlGaAsSb quantum cascade lasers grown lattice-matched on n-InP substrates is reported. By adjusting the As/Sb flux ratio as well as the group-III growth rate and the Al/Ga ratio for the AlGaAsSb layers, a growth technique has been optimized employing a continuous growth mode (i.e. no growth interruption) for the GaInAs/AlGaAsSb layer sequence of GaInAs/AlGaAsSb on InP quantum cascade structures. We found that the As/Sb incorporation ratio is determined by an interplay of arrival rate and chemical bonding of the involved species. The lasers operate in pulsed mode up to temperatures higher than 400 K, with a characteristic temperature of T(ind 0) = 169 K.