We demonstrate a superluminescent diode fabricated on a nonpolar ${m}$ -plane GaN substrate by employing a linearly tapered waveguide design. A high electrical −3dB modulation bandwidth ( $f_{\mathbf {3dB}}$ ) of 2.5 GHz at a current density of 30 kA/cm² is achieved. The high modulation bandwidth is attributed to the shorter carrier recombination lifetime, the linear gain curve in the nonpolar ${m}$ -plane quantum wells, and the ability to operate at high current densities while effectively suppressing lasing. We derive a general expression for the −3dB bandwidth as a function of current density for SLDs using a similar approach to that for laser diodes. The −3dB bandwidth of a nonpolar superluminescent diode increases exponentially with current density. The experimental results are consistent with the derived expression for $f_{\mathbf {3dB}}$ vs. current density.

中文翻译：

---

具有 2.5 GHz 调制带宽的高速非极性 InGaN/GaN 超辐射发光二极管

我们展示了在非极性材料上制造的超辐射发光二极管 ${m}$ 平面 GaN 衬底采用线性锥形波导设计。高电-3dB调制带宽（ $f_{\mathbf {3dB}}$ ) 在 30 kA/cm ²的电流密度下达到 2.5 GHz 。高调制带宽归因于较短的载流子复合寿命，非极性的线性增益曲线 ${m}$ 平面量子阱，以及在高电流密度下工作的能力，同时有效地抑制激光。我们使用与激光二极管类似的方法推导出 -3dB 带宽作为 SLD 电流密度的函数的一般表达式。非极性超辐射发光二极管的 -3dB 带宽随电流密度呈指数增长。实验结果与推导出的表达式一致 $f_{\mathbf {3dB}}$ 对比. 当前密度。