A novel scheme for the generation of an optical frequency comb with exceptionally high flatness for a large number of spectral lines is proposed. The scheme consists of a dual-parallel Mach–Zehnder modulator (DP-MZM) with which to carve the narrow intensity pulse and phase modulators for the application of high chirp. The experimental results show perfect spectral profiles with 35 lines with <1 dB flatness and 54 lines at 1.6 dB flatness when a DP-MZM is combined with two and three phase modulators, respectively.

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in brief

Highly flat optical comb generation based on DP-MZM and phase modulators

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