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arXiv · 2409.17719

Multi-Wavelength DFB Laser Based on Sidewall Third Order Four Phase-Shifted Sampled Bragg Grating with Uniform Wavelength Spacing

Xiao Sun·Zhibo Li·Yizhe Fan·Mohanad Jamal Al-Rubaiee·John H. Marsh·Anthony E Kelly·Stephen. J. Sweeney·Lianping Hou
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Abstract

We present the first demonstration of a 1550 nm multi-wavelength distributed feedback (MW-DFB) laser employing a third-order, four-phase-shifted sampled sidewall grating. By utilizing linearly chirped sampled gratings and incorporating multiple true {\pi}-phase shifts within the cavity, we achieved and experimentally validated a four-wavelength laser with a channel spacing of 0.4 nm. The device operates stably and uniformly across a wide range of injection currents from 280 mA to 350 mA. The average wavelength spacing was measured at 0.401 nm with a standard deviation of 0.0081 nm. Additionally, we demonstrated a 0.3 nm MW-DFB laser with a seven-channel output, achieving a wavelength spacing of 0.274 nm and a standard deviation of 0.0055 nm. This MW-DFB laser features a ridge waveguide with sidewall gratings, requiring only one metalorganic vapor-phase epitaxy (MOVPE) step and a single III-V material etching process. This streamlined fabrication approach simplifies device manufacturing and is well-suited for dense wavelength division multiplexing (DWDM) systems.

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Xiao Sun, Zhibo Li, Yizhe Fan, Mohanad Jamal Al-Rubaiee, John H. Marsh, Anthony E Kelly, Stephen. J. Sweeney, Lianping Hou. 2024-09-26. Multi-Wavelength DFB Laser Based on Sidewall Third Order Four Phase-Shifted Sampled Bragg Grating with Uniform Wavelength Spacing. https://arxiv.org/abs/2409.17719

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