Optimization of Electro-Optic Comb Generation Using Conventional Mach-Zehnder Modulator

We optimize electro-optic frequency comb generation using a conventional Mach-Zehnder modulator. It is theoretically and experimentally proved that a conventional Mach-Zehnder modulator can generate optical frequency comb with excellent spectral flatness. In this technique, the modulator is asymmetrically dual-driven by large-amplitude sinusoidal signals with different amplitudes. The optimal driving condition is theoretically derived, and translated to practical formulas. 10-GHz spaced ultraflat optical frequency comb generation with a 10-dB bandwidth of 230 GHz was demonstrated to confirm the concept.