All-polarization-maintaining fiber optical frequency comb for the dispersion measurement of a microcavity

Abstract

In this research, we demonstrate an optical frequency comb (OFC) based on a figure-9 laser and polarization-maintaining fibers to measure the dispersion of a microcavity. We adopt a multi-branch structure to obtain a broadband spectrum from 1,250 nm to 1,640 nm with 6-dB bandwidth. The single-mode power at each wavelength of the supercontinuum spectra is greater than 300 nJ, which assures the signal-to-noise ratio of the beat notes between the OFC and the diode laser. The frequency stability of the repetition rate is about 7.5 × 10–14 in an integration time of 1 s. This system allows us to extend the measurement bandwidth to 60 THz at the sub-megahertz resolution, which meets the requirements of the microcavity’s higher-order dispersion measurement.