60 GHz Bandwidth Directly Modulated Membrane III-V Lasers on SiO₂/Si

Increasing demand for higher data rates in data centers and high-performance computing systems require optical interconnects that support more than 100 Gbps-per-lane. Meanwhile, as optics are packed ever closer to Ethernet switches and electronic processors, both operating temperatures and power consumptions increase, resulting in increasing operational and environmental costs. In this work we present our recent results on a two-channel energy-efficient directly-modulated membrane laser array on SiO2/Si with ∼60-GHz 3-dB bandwidth, that can support both 100 Gbps-per-lane modulations as well as very small form-factors and power consumptions. The extension to 60 GHz bandwidths denotes a ∼26.3% increase compared to previous works, and it was achieved based on an optimized distributed-reflector laser design for maximizing the photon-photon resonance effect. Based on the fabricated two-channel DML array, 200 Gbps (2×112-Gbps NRZ) with laser operating energy-per-bit cost of less than 0.3 pJ/bit over 2-km transmissions, and the feasibility of 400 Gbps (2×200-Gbps PAM-4) transmissions are demonstrated. Finally, the temperature dependence of the PPR effect and its impact on the E-O response have been studied both experimentally and with numerical simulations for temperatures up to 75 °C for the first time.