Stroud Jasper R, Long David A, Plusquellic David F
Opt Lett. 2024 Jul 15;49(14):3878-3881. doi: 10.1364/OL.529147.
Dual optical frequency comb spectroscopy allows for high speed, broadband measurements without any moving parts. Here, we combine differential chirp downconversion to probe large spectral bandwidths and serrodyne modulation to separate the positive and negative sidebands in a single modulator. As an initial demonstration, we apply this approach to measure a sharp cavity resonance to illustrate the system performance. We then measure methane transitions in the near-infrared and compare the resulting spectra to models based upon the current spectroscopic databases. The serrodyne method has lower hardware requirements compared to many existing approaches, and its simplicity enables a high degree of mutual coherence between the two combs. Further, this method is readily amenable to chip-scale photonic integration.
双光频梳光谱技术能够实现高速、宽带测量，且无需任何移动部件。在此，我们将差分啁啾下变频与锯齿波调制相结合，以探测大光谱带宽，并在单个调制器中分离正负边带。作为初步演示，我们应用此方法测量尖锐的腔共振，以说明系统性能。然后，我们测量近红外波段的甲烷跃迁，并将所得光谱与基于当前光谱数据库的模型进行比较。与许多现有方法相比，锯齿波方法对硬件的要求更低，其简单性使得两个光频梳之间具有高度的相互相干性。此外，该方法易于实现芯片级光子集成。
