PbEuSeTe buried heterostructure lasers grown by molecular‐beam epitaxy

The successful preparation of lattice matched buried heterostructure (BH)PbEuSeTe lasers grown by molecular‐beam epitaxy (MBE) is reported here for the first time. Lasers with 2–8 μm wide and 0.5 μm thick buried Pb1−xEuxSeyTe1−y active layers, in the composition range of 0≤x≤0.015 and cavity lengths between 200 and 300 μm, were fabricated. Single mode operation was realized in most devices for injection currents 1.2 to 4.5 times the threshold current. A maximum continuous wave (cw) operation temperature of 180 and 176 K was measured for BH diode lasers with PbTe and PbEuSeTe (0.22 at. % Eu) active layer compositions, respectively. Using a high‐resolution scanning electron microscope, growth discontinuities were found in the nonplanar regions of the second cladding and capping layers. In most cases, lower threshold current densities were measured for BH lasers in comparison to double heterostructure (DH) lasers with the same active layer composition. It is believed that improvement of growth morphology, an...