Dual-wavelength laser diodes based on epitaxially stacked heterostructures

AlGaAs/GaAs double laser heterostructures containing two different active regions have been grown by metalorganic vapour phase epitaxy in a single growth process, and their properties have been studied. A typical slope of their power — current curves is 2.3 W A^-1, which is almost twice that for a laser diode (1.2 W A^-1). We demonstrate lasing of the emitter regions of the dual-wavelength lasers in the range 800 — 815 nm, with a separation between the peaks of ~7 nm. The observed effect of pump current on the lasing wavelength of the active regions in the dual-wavelength and single lasers indicates that the emitter region farther away from the heat sink is more sensitive to pump current variations.