WAVELENGTH SWITCHING IN NARROW OXIDE STRIPE INGAAS-GAAS-ALGAAS STRAINED-LAYER QUANTUM-WELL HETEROSTRUCTURE LASERS

We have observed current-controlled wavelength switching in narrow oxide stripe In0.17Ga0.83As-GaAs-Al0.20Ga0.80As strained-layer single quantum well heterostructure lasers. Laser emission switches from the lowest (n = 1) quantized state transition in the quantum well at low currents to the first excited state transition (n = 2) at higher currents, with an energy difference of almost-equal-to 50 meV. For currents near the switching point, we have also observed time-dependent lasing behavior, with a switch in the laser emission from the n = 1 to the n = 2 transition. The order of this temporal switching (from n = 1 to n = 2) is opposite that observed in narrow stripe gain-guided GaAs-AlGaAs quantum well lasers, due to strong antiguiding in InGaAs lasers, which negates the effect of a thermal guide.