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Full-band tunable V-cavity laser for low-cost access and data center networks

The principle, design and experimental results of widely tunable V-cavity lasers are reviewed. By using a novel half-wave coupler, single-mode lasing with high side-mode-suppression-ratio is achieved. Single-electrode controlled wideband wavelength tuning is realized by employing the Vernier mechanism. The tuning range can be further extended beyond the free spectral range limit by using the effect of temperature induced gain spectrum shift. The full-band tuning of 50 channels with 100 GHz spacing is demonstrated at 1550 nm range. Similarly, 41-channel tuning with 150 GHz spacing is achieved at 870 nm. The advantages of compactness, fabrication simplicity, and easy wavelength control offer great potential for the tunable laser to be used in low-cost access and data center networks.