STRAINED QUATERNARY GAINASP QUANTUM-WELL LASER EMITTING AT 1.5 MU-M GROWN BY GAS SOURCE MOLECULAR-BEAM EPITAXY

Quantum well structures and separate confinement heterostructure lasers based on strained quaternary Ga1-xInxAs1-yPy well material were grown by gas source molecular beam epitaxy. The substitution of As for P allows a simultaneous control of wavelength, well width and strain in the structure. Single strained layers in InP show photoluminescence with narrow linewidth (4 to 8 meV). Broad area lasers with strained and unstrained layers have been grown with five quantum wells and identical optical confinement. The strained quaternary structure has a threshold current density of 760 A/cm2 for L = 400-mu-m, an internal quantum efficiency of nearly 100%, a waveguide loss of 10 cm-1 and a high T0 value (T0 = 91 K). Single-well structures have a lowest value of 240 A/cm2 for 3 mm long devices.