Monolithic quantum-dot distributed feedback laser array on silicon

TL;DR

This paper presents the first electrically-pumped, room-temperature quantum-dot DFB laser array on silicon, achieving low threshold currents, high side mode suppression, and broad wavelength coverage suitable for CWDM systems.

Contribution

It demonstrates the first monolithic quantum-dot DFB laser array on silicon with record performance metrics for CWDM applications.

Findings

Achieved CW threshold currents as low as 12 mA

Single-mode side mode suppression ratios up to 50 dB

Wavelength coverage of 100 nm in the O-band

Abstract

Electrically-pumped lasers directly grown on silicon are key devices interfacing silicon microelectronics and photonics. We report here, for the first time, an electrically-pumped, room-temperature, continuous-wave (CW) and single-mode distributed feedback (DFB) laser array fabricated in InAs/GaAs quantum-dot (QD) gain material epitaxially grown on silicon. CW threshold currents as low as 12 mA and single-mode side mode suppression ratios (SMSRs) as high as 50 dB have been achieved from individual devices in the array. The laser array, compatible with state-of-the-art coarse wavelength division multiplexing (CWDM) systems, has a well-aligned channel spacing of 20 0.2 nm and exhibits a record wavelength coverage range of 100 nm, the full span of the O-band. These results indicate that, for the first time, the performance of lasers epitaxially grown on silicon is elevated to a point approaching real-world CWDM applications, demonstrating the great potential of this technology.