Yu Mengjie, Okawachi Yoshitomo, Griffith Austin G, Lipson Michal, Gaeta Alexander L
Opt Lett. 2017 Nov 1;42(21):4442-4445. doi: 10.1364/OL.42.004442.
We report the first demonstration of a microresonator-based tunable mode-locked frequency comb source. We achieve a mode-hop-free tuning range of 16 GHz by simultaneously tuning both the pump laser and the cavity resonance while keeping the system in a multi-soliton mode-locked state. The optical spectrum spans 2520-4125 cm (2.425-3.970 μm) pumping at 3508 cm (2.850 μm) in a silicon microresonator with a comb line spacing of 4.23 cm (127 GHz). Our scanning technique can be used to increase the effective resolution of the microresonator-based comb spectroscopy. As a proof-of-principle demonstration, we record the absorption spectrum of the rovibrational transitions of the υ and υ+(υ+υ)+0 bands of acetylene. We measure absorption features as narrow as 0.21 cm (6.4 GHz) full width at half-maximum at a frequency sampling step of 80 MHz.
我们报道了首个基于微谐振器的可调谐锁模频率梳源的演示。通过在保持系统处于多孤子锁模状态的同时，对泵浦激光器和腔共振进行同步调谐，我们实现了16 GHz的无模式跳变调谐范围。在梳状线间距为4.23 cm（127 GHz）的硅微谐振器中，以3508 cm（2.850 µm）泵浦时，光谱范围为2520 - 4125 cm（2.425 - 3.970 µm）。我们的扫描技术可用于提高基于微谐振器的梳状光谱学的有效分辨率。作为原理验证演示，我们记录了乙炔的υ和υ +（υ + υ）+ 0带的振转跃迁吸收光谱。在80 MHz的频率采样步长下，我们测量到半高宽窄至0.21 cm（6.4 GHz）的吸收特征。
