1060-nm single-mode transverse coupled cavity VCSEL with intra-cavity surface relief for 58-Gbps modulation and 5-km single-mode fiber transmission

In this Letter, we report a 1060-nm vertical-cavity surface-emitting laser with intra-cavity surface relief engineering that provides transverse-resonance in transverse-coupled cavities, enabling single-mode operation and bandwidth enhancement at the same time. A single-mode power of over 2.5 mW and 3-dB modulation bandwidth enhancement from 15 to 23 GHz was demonstrated with an oxide aperture diameter as large as 6 μm. We obtained non-return-to-zero signals of up to 58 Gbps with eye-opening through a 5-km long standard single-mode fiber (G652). The 3-dB modulation bandwidth is enhanced by the negative dispersion of the fiber and pre-equalization via calibration of the end-to-end channel response. Our device shows great potential for its use in high-speed and compact optical transmitters in the next-generation hyper-scale datacenters and 6G network.