Strained GaInAs-AlGaInAs 1.5-μm-wavelength multiquantum-well lasers loaded with GaInAs-AlInAs multiquantum barriers at the p-side optical confinement layer

Compressively strained GaInAs-AlGaInAs multiquantum-well (MQW) lasers (LD´s) operating at 1.5-μm-wavelength were fabricated with a multiquantum barrier (MQB) structure at the p-side of the optical confinement layer, using molecular beam epitaxial (MBE) growth technology. The effect of loading MQB is demonstrated from both laser performances and electro-luminescence (EL) spectra from LD´s. As evidence of the suppression of carrier overflow by loading of MQB, it was confirmed from the laser performances that 1) the temperature dependence of slope efficiency was improved so that the efficiency was increased at high temperature and the maximum operating temperature was raised about 15°C, 2) the temperature dependence of the K factor was improved, and the K factor was reduced more than 30% at high temperature. More direct evidence was observed in EL spectra from LD´s. Reduction of about one magnitude was confirmed in the peak intensity of EL from the optical confinement layer. The rate of suppression of carrier overflow is discussed from above EL reduction rate