Abstract A graded-compositional waveguide structure is proposed to improve the optical field distribution of InGaN-based green laser diodes (LDs). It is found that the optical field leaking into the GaN substrate is suppressed obviously when using the graded-compositional upper and lower waveguide. Owing to the enhancement of refractive index contrast between the waveguide layer and the cladding layer, the optical field confinement factor increases, and the optical field is more concentrated near the active region. Besides, higher output power and lower threshold current are achieved due to reduced electron leakage and increased hole injection. This work provides a theoretical design method for obtaining high-performance InGaN-based green LDs.

中文翻译：

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通过梯度组成波导结构改善 InGaN 基绿色激光二极管的光学和电学性能

摘要 为了改善InGaN基绿光激光二极管(LD)的光场分布，提出了一种渐变复合波导结构。研究发现，采用渐变组成的上下波导时，泄漏到GaN衬底的光场得到了明显的抑制。由于波导层和包覆层之间的折射率对比度增强，光场限制因子增加，光场更集中在有源区附近。此外，由于电子泄漏减少和空穴注入增加，实现了更高的输出功率和更低的阈值电流。这项工作为获得高性能 InGaN 基绿色 LD 提供了一种理论设计方法。