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Single-modulator, direct frequency comb spectroscopy via serrodyne modulation



David Long, Sean Bresler, Yiliang Bao, Benjamin Reschovsky, Thomas W. LeBrun, Jason J. Gorman


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.
Optics Letters


Optical frequency comb, accelerometry, serrodyne


Long, D. , Bresler, S. , Bao, Y. , Reschovsky, B. , LeBrun, T. and Gorman, J. (2023), Single-modulator, direct frequency comb spectroscopy via serrodyne modulation, Optics Letters, [online], (Accessed April 19, 2024)
Created February 3, 2023, Updated February 16, 2024