A 53-Gbaud NRZ/PAM4 × 8-Channel 1060-nm Single-Mode VCSEL-Based Ultra-Compact and High-Energy-Efficient CPO Transceiver for Full-Reach Datacenter Links

We demonstrate an ultra-compact (1.22 cm 2 footprint), high-energy-efficient (4.5 pJ/bit), 53-Gbaud × 8-channel 1060-nm SM VCSEL-based CPO transceiver enabling 2-km SMF parallel links. A newly designed two-microlens-array coupling system achieves <2 dB loss.