TUNNELING INJECTION-LASERS - A NEW CLASS OF LASERS WITH REDUCED HOT-CARRIER EFFECTS

In conventional quantum-well lasers, carriers are injected into the qu antum wells with quite high energies. We have investigated quantum-wel l lasers in which electrons are injected into the quantum-well ground state through tunneling. The tunneling injection lasers are shown to h ave negligible gain compression, superior high-temperature performance , lower Anger recombination and wavelength chirp, and better modulatio n characteristics when compared to conventional lasers. The underlying physical principles behind the superior performance are also explored , and calculations and measurements of relaxation times in quantum wel ls have been made, Experimental results are presented for lasers made with a variety of material systems, InGaAs-GaAs-AlGaAs, InGaAs-GaAs-In GaAsP-InGaP, and InGaAs-InGaAsP-InP, for different applications, Both single quantum-well and multiple quantum-well tunneling injection lase rs are demonstrated.