Opt Lett. 2023 Feb 15;48(4):892-895. doi: 10.1364/OL.482597.
Traditional electro-optic frequency comb spectrometers rely upon the use of an acousto-optic modulator (AOM) to provide a differential frequency shift between probe and local oscillator (LO) legs of the interferometer. Here we show that these modulators can be replaced by an electro-optic phase modulator (EOM) which is driven by a sawtooth waveform to induce serrodyne modulation. This approach enables direct frequency comb spectroscopy to be performed with a single dual-drive Mach-Zehnder modulator (DD-MZM), allowing for lower differential phase noise. Further, this method allows for simpler production of integrated photonic comb spectrometers on the chip scale.
传统的电光频梳光谱仪依赖于声光调制器 (AOM) 在干涉仪的探头和本振 (LO) 支路之间提供差分频率移动。在这里，我们展示了这些调制器可以被电光相位调制器 (EOM) 取代，EOM 由锯齿波驱动以产生类正弦调制。这种方法使直接频梳光谱学能够用单个双驱动马赫-曾德尔调制器 (DD-MZM) 来实现，从而降低了差分相位噪声。此外，这种方法允许在芯片级上更简单地制作集成光子梳状光谱仪。
