We use a drift-diffusion model that includes the effect of bleaching to study the impact of nonlinear distortion in a p-i-n photodetector (PD) on RF-modulated frequency combs. This work complements a similar study that we carried out for a modified uni-traveling carrier (MUTC) PD. We begin by using experimental responsivity data to develop an empirical model of the bleaching in a p-i-n PD when operating in pulsed mode. We then incorporate this model of bleaching into a drift-diffusion model. Next, we use this drift-diffusion model to determine the impact of nonlinearity on the second- and third-order intermodulation distortion products IMD2n and IMD3n as a function of the comb line number n. We then determine the corresponding output intercept points OIP2n and OIP3n and distortion-to-signal ratios ρ2n and ρ3n. In contrast to MUTC devices, we find that bleaching increases ρ2n and ρ3n at all comb line numbers. However, these distortion products change little as n increases, in contrast to MUTC devices where they grow rapidly as n increases.

中文翻译：

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非线性影响（包括 $p$-$i$-$n$ 光电探测器中的漂白）对射频调制电光频率梳的影响


我们使用包含漂白效应的漂移扩散模型来研究 pin 光电探测器 (PD) 中的非线性失真对 RF 调制频率梳的影响。这项工作补充了我们对改进的单程承运人 (MUTC) PD 进行的类似研究。我们首先使用实验响应率数据开发在脉冲模式下操作时针 PD 漂白的经验模型。然后，我们将这种漂白模型合并到漂移扩散模型中。接下来，我们使用该漂移扩散模型来确定非线性对二阶和三阶互调失真产物 IMD2n 和 IMD3n 的影响，作为梳线数 n 的函数。然后，我们确定相应的输出截点 OIP2n 和 OIP3n 以及失真信号比 ρ2n 和 ρ3n。与 MUTC 设备相比，我们发现漂白增加了所有梳线数的 ρ2n 和 ρ3n。然而，这些失真产物随着 n 的增加而变化很小，而 MUTC 器件则随着 n 的增加而迅速增长。