AlGaInP multiple-quantum-wire lasers grown by gas source molecular beam epitaxy

Abstract

GaxIn1−xP/Al0.15Ga0.35In0.5P graded-index separate-confinement heterostructure visible laser structures with multiple quantum wire active regions have been formed in situ during gas source molecular beam epitaxy. No regrowths or ex situ fabrication procedures were employed in the formation of the quantum wires. Quantum wires with cross-sectional dimensions of approximately 50×120 Å were routinely achieved with a linear density of 100/μm. Broad area stripe geometry lasers with contact stripe oriented in the [110] and [1̄10] directions exhibited anisotropic threshold current densities varying in ratio by a factor of more than 3.75. Threshold current densities as low as 400 A/cm2 were obtained for lasers with stripes in the [110] direction, perpendicular to the quantum wires. Strong dependence of electroluminescence polarization on stripe direction was also observed.