Gain coefficient, quantum efficiency, transparency current density, and internal loss of the AlGaAs-GaAs-based lasers on Si substrate

The AlGaAs-GaAs based lasers on Si substrate with GaAs quantum-well and island-like active regions are fabricated by metal-organic chemical vapor deposition. The parameters of internal quantum efficiency, gain coefficient, transparency current density, and the internal loss that describe the operating characteristics of laser diodes are investigated. The optical confinement factor is calculated with the assumption that the light emission occurs from the island regions only. In addition, longer minority carrier lifetime obtained for the lasers with island-like active regions reveals their improved characteristics over conventional quantum-well lasers.