Effect of Composition Step-Graded InGaN Barriers on Photoelectric Performance of Green Laser Diode.

In order to investigate the influence of InxGa1-xN barrier with different indium ( In) composition on photoelectric performance of green laser diode, a series of green laser diode with InxGa1-xN barrier of different In composition were simulated by SiLENSe ( simulator of light emitters based on nitride semiconductors) software. The results show that the InxGa1-xN barrier structure with 3% In composition has the highest slope efficiency and the lowest internal optical loss, and also show the largest optical confinement factor and the optimum performance. Based on the multiple quantum well structure with In0.03Ga0.97N barrier, the composition step-graded (CSG) InGaN barrier model structure was designed, which effectively improves the slope efficiency and electro-optical conversion efficiency. Moreover, the optical field confinement increase. The simulation results show that at the injection current of 120 mA, the efficiency of electro-optical conversion increases from 17.7% to 19. 9% for the multiple quantum well structure with CSG InGaN barrier, the slope efficiency increases from 1. 09 mW/mA to 1. 14 mW/mA, and the optical confinement factor increases from 1. 58% to 1. 62%. The study provides theoretical guidance and data support for the preparation of high-power GaN-based green laser diode. [ABSTRACT FROM AUTHOR]