On the fabrication and study of lattice-matched heterostructures for quantum cascade lasers

The fabrication and study of the characteristics of a lattice-matched quantum cascade laser structure on an indium-phosphide substrate, designed for a wavelength of $\sim$4.8 $\mu$m corresponding to one of the atmospheric windows are described. The heterostructure grown by molecular-beam epitaxy consisted of thirty cascades. Lasing was experimentally observed at temperatures up to 200 K at a wavelength coinciding with the calculated one, which confirms the high heterointerface quality and high precision of the layer thicknesses and active-region doping levels.