Effect of InGaP Barrier Thickness on the Performance of 1.3-µm InAsP/InP/InGaP Strain-Compensated Multiple-Quantum-Well Laser Diodes

We report the effect of InGaP barrier thickness on the performance of 1.3-mum InAsP/InP/InGaP strain-compensated multiple-quantum-well (SC-MQW) ridge waveguide laser diodes (LDs) grown by metalorganic chemical vapor deposition. By increasing the InGaP tensile-strained barrier thickness to above 6 nm in the InAsP/InP/InGaP SC-MQW structure, a redshift of the photoluminescence peak position can be observed duo to the redistribution across the samples of the huge built-in electric field induced by the piezoelectric effect. By using the optimum thickness of 2 nm InGaP barrier layer, the threshold current decreases from 78.5 to 41.5 mA and the characteristic temperature significantly increases as compared to those of the strain-uncompensated LDs. These results indicate that an adequate thickness of tensile-strained InGaP barrier is necessary to be employed to compensate the compressive strain in the InAsP/InP alloy system for optoelectronic devices.