Low Cost, Low Power, Low Latency 1602 nm 100 Gbps NRZ Laser–EAM for a 7.2 Tbps Transmitter.

The need for higher speed supercomputing power at NASA is clear, and one of the many impairments to realizing an exaflop computer is the speed and latency of the data links that connect the processors and memory. Even with the advent of higher speed standards in Ethernet and Fibre Channel, the data throughput is crippled due to the need for non-binary encoding and error correction algorithms as a direct result of the limited bandwidth of the optical components. The induced latency and power consumption are acceptable in a data center environment but severely limits high performance computing. Efforts to increase the fundamental optical component bandwidth have not been successful in increasing to the point of achieving binary NRZ data transmission without error correction at 100Gbps. Binary NRZ is the most power and latency efficient means to transmit data in a super computing environment. A revolutionary optical component is needed to break the traditional paradigm. The laser and electro-absorptive modulator (laser-EAM) in this proposal represents many significant technical advancements including: (1) fundamental bandwidth in excess of 100GHz using direct band to band absorption, (2) very low power consumption (lt;150fJ/bit), (3) operation over the entire environmental temperature range without a thermo-electric controller, (4) monolithic integration of the laser and EAM (5) potential to integrate a vertical outcoupler. The innovations that lead to these technical achievements are the design of a common active region for both the laser and EAM, and the use of enhanced coupling strength (ECS) gratings to provide wideband mirrors. This combination allows the laser emission to tune freely with temperature and the EAM absorption to track the laser. Further, the laser-EAM is realized in a single epitaxial growth, and the fabrication is completely monolithic. This provides a highly manufacturable and cost-effective solution to the optical component bandwidth problem.