Enabling the Future of High-Performance Computing and AI with Ayar Labs' TeraPHY Optical I/O Technology

Terence S.-Y. Chen, Latitude Design Systems

Abstract

This white paper provides an overview of Ayar Labs' innovative TeraPHY optical input/output (I/O) solution and how it can revolutionize high-performance computing (HPC) and artificial intelligence (AI) systems by overcoming the limitations of electrical I/O. The TeraPHY technology offers unprecedented bandwidth density, power efficiency, and low latency using silicon photonics to enable direct chip-to-chip optical connections. We discuss the key features and benefits of the TeraPHY chiplet and SuperNova light source, applications across HPC, AI, data centers, networking, and defense, and the reliability advantages of the optical I/O approach.

Figure 1. The 4Tbps configuration that Ayar Labs demonstrated. Image courtesy of Ayar Labs.

Introduction

High-performance computing and artificial intelligence have become critical strategic technologies, enabling innovations across science, medicine, business, and defense. However, the growth of HPC and AI systems is increasingly constrained by interconnect bottlenecks, power limitations, and costs. Electrical I/O technologies like copper wires and pluggable optics fail to provide the required bandwidth density, energy efficiency, latency, and scalability for future systems.

Ayar Labs has developed a breakthrough solution to this problem: TeraPHY optical I/O technology. TeraPHY combines electronic and photonic elements on a silicon chiplet that can be integrated into standard chip packages. Along with Ayar's SuperNova multi-wavelength light source, TeraPHY enables direct optical connections between chips, providing massive bandwidth, ultra-low latency, and power efficiency that is unmatched by electrical I/O.

This white paper explains the key capabilities of TeraPHY optical I/O, its applications and benefits, and why it represents a transformative change for future computing systems.

TeraPHY Optical I/O: A Technical Overview

Ayar Labs' TeraPHY optical I/O chiplet combines electronic and photonic components on a CMOS-compatible silicon substrate using the company's proprietary monolithic fabrication process. This enables dense integration of high-speed optical I/O ports right next to the electronics die inside a standard chip package.

The TeraPHY chiplet works with Ayar's SuperNova multi-wavelength laser source, which can be located remotely and coupled to the chip package through optical fiber cables. This provides a complete optical I/O solution: the SuperNova generates many wavelengths of light, while the TeraPHY modulates and receives this light to transmit and receive data.

Key capabilities and benefits of this TeraPHY I/O solution include:

• Extreme bandwidth density: Up to 2 Tbps bandwidth per chiplet, or 200 Gbps per mm of chip edge. 1000x greater than electrical I/O;

• Ultra-low latency: 5 ns per chiplet, 10x faster than electrical. Enables real-time processing;

• High energy efficiency: <5 pJ/bit, 10x more efficient than electrical I/O. Reduces power and cooling costs;

• Flexible reach: From die-to-die to rack-to-rack. Millimeters to kilometers;

• High reliability: GR-468 compliant, resilient to noise, EMI, voltage fluctuations.

Together, TeraPHY and SuperNova provide the capacity, speed, efficiency, and robustness needed to overcome the interconnect bottlenecks in next-generation HPC and AI systems.

Figure 2. The 4Tbps configuration that Ayar Labs demonstrated. Image courtesy of Ayar Labs.

Revolutionizing HPC and AI Systems

The extreme bandwidth density and low latency of Ayar's optical I/O technology can enable transformative leaps in HPC and AI application performance:

• Training complex AI models like GPT-3 in hours instead of weeks;

• Reducing time-to-solution for HPC workloads by 10x or more;

• Enabling real-time AI inferencing for critical applications;

• Scaling out AI and HPC systems to exascale capacities.

Specific use cases that can benefit from TeraPHY optical I/O include:

• Connecting GPU/TPU arrays for massively parallel AI training and inferencing;

• Low-latency coupling of CPUs, memory, storage, accelerators, and networking;

• Rack-scale disaggregated computing with flexible resource pooling;

• Chip-to-chip interconnects for HPC, networking, and embedded processors;

• Next-gen wireless, lidar, and satellite networks.

The extreme bandwidth capacity of a single TeraPHY chiplet (2 Tbps) can replace hundreds of electrical IO or optic fibers. This reduces costs, complexity, and power consumption.

Combining the economics, performance, and flexibility of co-packaged optics, Ayar's solution helps make real-time AI, personalized medicine, intelligent wireless, and other future applications viable and accessible.

Reliability: A Key Advantage of Optical I/O

Ayar Labs' TeraPHY optical I/O solution offers inherent reliability and robustness benefits over electrical I/O:

• Immune to electromagnetic interference that can corrupt electrical signals;

• Lower thermal resistance for better heat dissipation;

• Tolerant of power supply noise and fluctuations;

• GR-468 compliant for optoelectronic reliability under extreme conditions

• Monolithic integration reduces defects versus assembling discrete components;

By transmitting data as light through fiber rather than electrical signals across copper, optical I/O avoids many common failure mechanisms in HPC and networking systems. This improves uptime, reduces maintenance costs, and extends system lifetime.

PIC Studio

PIC Studio can potentially support the development of products similar to Ayar Labs' optical I/O solution:

• PIC Studio provides a full set of integrated schematic capture, simulation, and layout tools for photonic IC design, which could facilitate the design and verification of optical transceiver chiplets like Ayar's TeraPHY. The schematic-driven layout capability could also improve designer productivity;

• The pSim circuit simulator supports key analyses needed for optical transceiver design, including time/frequency domain, modulation, and fiber link simulations. This could help model and optimize the performance of Ayar-like optical I/O links;

• PIC Studio enables co-simulation of photonics with electronics, which is critical for modeling the interface between the photonic chiplet and electronic die. This could help ensure proper functioning of the optical I/O solution;

• The open interfaces in PIC Studio allow integration with other simulation tools like FDTD, TCAD, and Spice. This modeling flexibility could assist in multi-physics analysis and verification of the optical packaging;

• PIC Studio has PDK support from multiple silicon photonic foundries. This could provide manufacturing options for fabricating Ayar-like chiplets;

• The availability of design tutorials for circuits like optical modulators and coherent transceivers suggests PIC Studio has the capabilities to support development of optical I/O links.

PIC Studio appears well-suited for designing and verifying silicon photonic transceiver chiplets and packages similar to Ayar Labs' technology. The integrated workflow and simulation capabilities could improve engineering efficiency. PIC Studio's flexibility would allow modeling the performance of Ayar-like products.

Conclusion

Ayar Labs' TeraPHY optical I/O represents a giant leap forward for high-performance interconnects. Offering massive bandwidth, low latency, efficiency, reach, and reliability, TeraPHY and SuperNova overcome the limitations of electrical I/O to enable the next generation of computing and AI systems. With its innovative silicon photonics and packaging solutions, Ayar Labs paves the way for organizations to accelerate discovery, unlock insights, and deploy new intelligent services.