Multi-wavelength 128 Gbit s⁻¹ λ ⁻¹ PAM4 optical transmission enabled by a 100 GHz quantum dot mode-locked optical frequency comb

Abstract Semiconductor mode-locked lasers (MLLs) with extremely high repetition rates are promising optical frequency comb (OFC) sources for their usage as compact, high-efficiency, and low-cost light in high-speed dense wavelength-division multiplexing transmissions. The fully exploited conventional C- L- bands require the research on O-band to fulfil transmission capacity of current photonic networks. In this work, we present a passive two-section InAs/InGaAs quantum-dot (QD) MLL-based OFC fundamental rate ∼100 GHz operating at wavelength range. specially designed device favours generation nearly Fourier-transform-limited pulses entire test range by only pumping gain section while absorber unbiased. typical integrated relative intensity noise whole spectrum single tone −152 −137 dB Hz −1 100 MHz–10 GHz, respectively. Back-to-back data transmissions seven selected tones have been realised employing 64 Gbaud four-level pulse amplitude modulation format. demonstrated performance shows feasibility InAs QD MLLs simple structure, easy operation, low power consumption fibre-optic communications.