Passive harmonic mode-locking by mode selection in Fabry-Perot diode lasers with patterned effective index

TL;DR

This paper demonstrates a method for passive harmonic mode-locking in quantum well laser diodes by using patterned effective index to select specific modes, resulting in high-repetition-rate pulsed output.

Contribution

It introduces a novel spectral filtering technique via cavity patterning to achieve harmonic mode-locking in Fabry-Perot lasers.

Findings

Achieved 2 ps pulse duration at 100 GHz repetition rate.

Successfully selected six modes spaced at twice the fundamental frequency.

Demonstrated near-transform limited pulsed output.

Abstract

We demonstrate passive harmonic mode-locking of a quantum well laser diode designed to support a discrete comb of Fabry-Perot modes. Spectral filtering of the mode spectrum was achieved using a non-periodic patterning of the cavity effective index. By selecting six modes spaced at twice the fundamental mode spacing, near-transform limited pulsed output with 2 ps pulse duration was obtained at a repetition rate of 100 GHz.