Quantum dot lasers on silicon have gained significant interest over the past decade due to their great potential as an on-chip silicon photonic light source. Here, we demonstrate multi-wavelength injection locking of InAs/GaAs quantum dot Fabry–Perot (FP) lasers both on GaAs and silicon substrates by optical self-injection via an external cavity. The number of locked laser modes can be adjusted from a single peak to multiple peaks by tuning wavelength dependent phase and mode spacing of back-injected light through a Lyot filter. The multi-wavelength injection locked laser modes exhibit average optical linewidth of ∼20 kHz$\sim 20\mathrm{kHz}$, which are narrowed by approximately three orders of magnitude from their free-running condition. Furthermore, multi-wavelength self-injection locking via an external cavity exhibits flat-top optical spectral properties with approximately 30 stably locked channels under stable operation over time, where the frequency detuning is less than 700 MHz within 40 min. Particularly, FP lasers by direct epitaxial growth on silicon substrates are self-injection locked as a flat-top comb source with tunable free spectral range from approximately 25 to 700 GHz. The reported results emphasize the great potential of multi-wavelength injection locked lasers as tunable on-chip multi-wavelength light sources.

中文翻译：

---

多波长注入锁定半导体梳状激光器

在过去十年中，硅上的量子点激光器因其作为片上硅光子光源的巨大潜力而​​引起了人们的极大兴趣。在这里，我们展示了通过外腔光学自注入在 GaAs 和硅衬底上的 InAs/GaAs 量子点法布里-珀罗 (FP) 激光器的多波长注入锁定。通过调整通过 Lyot 滤光片的反向注入光的波长相关相位和模式间隔，可以将锁定激光模式的数量从单个峰值调整为多个峰值。多波长注入锁定激光模式的平均光学线宽约为20 kHz $\sim 20\mathrm{kHz}$，它们从它们的自由运行状态缩小了大约三个数量级。此外，通过外腔的多波长自注入锁定表现出平顶光谱特性，随着时间的推移，在稳定运行的情况下，大约有 30 个稳定锁定的通道，其中频率失谐在 40 分钟内小于 700 MHz。特别是，通过在硅衬底上直接外延生长的 FP 激光器被自注入锁定为平顶梳状光源，具有大约 25 至 700 GHz 的可调自由光谱范围。报告的结果强调了多波长注入锁定激光器作为可调谐片上多波长光源的巨大潜力。