The properties of microscopic semiconductor lasers with external optical feedback are theoretically analysed. The size-dependence of the critical feedback level, at which the laser first becomes unstable, is clarified, showing how the dominant indicator of feedback stability is the gain of the laser, irrespective of size. The impact of increased spontaneous emission β-factors and over-damped operation is evaluated, exposing a diminished phase sensitivity of microscopic lasers, and a trade-off between modulation bandwidth and feedback stability is identified.

中文翻译：

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具有外部光反馈的微观半导体激光器的理论

理论上分析了具有外部光反馈的微观半导体激光器的性能。阐明了激光首先变得不稳定时的临界反馈水平的大小依赖性，表明了反馈稳定性的主要指标如何成为激光器的增益，而与大小无关。评估了增加的自发发射β因子和过阻尼操作的影响，暴露了微观激光的相位灵敏度降低，并确定了调制带宽和反馈稳定性之间的折衷方案。