Initiative in optical computing may lead to advances in artificial intelligence (AI) and thermal management

Summary points:

• DARPA is seeking industry input for the Very Large-scale Photonic Integration (VLPI) project, aimed at revolutionizing computing through large-format photonic integrated circuits.
• Using light instead of electricity could enable data processing speeds 10 million times faster than traditional electronics, with dramatically lower energy use and thermal output.
• VLPI could lead to advances in AI, ISR, command and control, and battlefield systems -- echoing the historic influence of DARPA’s VLSI and VHSIC programs of the 1970s and 1980s.

THE MIL & AERO COMMENTARY – We're on the verge of a new era in high-performance military computing and data networking that could offer unprecedented advantages in extreme data throughput and bandwidth; small size, weight, and power (SWaP); and low power consumption. Affording this are new developments in optical computing.

This design approach capitalizes on the intensity, phase, polarization, and wavelengths of light to encode, process, and transmit information in applications like artificial intelligence (AI), data processing, data storage, and communications.

Earlier this month the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., approached industry with a request for information (DARPA-SN-25-88) for the Very Large-scale Photonic Integration (VLPI) project.

VLPI seeks to develop new approaches to manufacturing optical integrated circuits in large-format wafers for power-efficient computing that requires little thermal management compared to today's high-performance processors.

Photonic computing at-scale

Developing VLPI integrated circuits at scale could unleash entirely new computational approaches to intelligence, surveillance, reconnaissance, automatic target recognition, predictive maintenance and logistics, battlefield command and control, and other computationally intensive aerospace and defense applications.

If you've been around long enough, VLPI probably sounds familiar; it's reminiscent of a military research project in the late 1970s to improve Very Large Scale Integration (VLSI) integrated circuit technology.

The VLSI program led to microprocessor and computing innovations for the time like the Unix BSD software operating system, the RISC processor architecture, new computer-aided design tools, 32-bit graphics workstations, and other advanced microelectronics that enhanced national security and commercial computing applications.

The VLSI program led to other ground-breaking initiatives in microelectronics design, such as the Very Large Scale Integration (VHSIC) project and later the Monolithic Microwave Integrated Circuit (MMIC) project that developed advanced integrated circuit design, fabrication, and automation tools for today's high-speed and specialized integrated circuits.

Tell me more about optical computing.

• Optical computing, also called photonic computing, uses light -- specifically photons produced by lasers or other sources -- rather than electrons to perform computations, data processing, and data storage. Instead of electrical signals in conventional computers, optical computing capitalizes on properties of light such as intensity, phase, polarization, and wavelength to encode and process information.

The VLPI program has the potential to revolutionize integrated circuit design in much the same way as the VLSI program did nearly 50 years ago. It will explore the feasibility, manufacturability, and application of very large-scale photonic circuits for future communications, sensing, and computer systems using light-based components.

Optical computing, compared to electronic computing, uses photons instead of electronics to process and move data. Some estimates suggest optical computing can work 10 million times faster than today's electronic computers, which could reduce computations taking years to just hours.

It offers substantially higher bandwidth and faster information transfer electronic computers because photons can travel faster and with less energy loss than electrons.

Optical computing also is immune to electromagnetic interference, free from electrical short circuits, and can handle parallel data processing more easily than electronic systems. It also doesn't generate as much waste heat as electronic computers, which could reduce the load on thermal management and electronics cooling subsystems.

Understanding capabilities

For the early stages of the VLPI program, DARPA is seeking to understand what capabilities might come from advanced photonic integrated circuit technology, today's state of the art, and to determine what remaining technological barriers remain in the design of such circuits.

It seeks to enable fabrication of high-performance photonic integrated circuits in large-format wafers. Light-based processing can be extremely fast, energy efficient, and lighten the load for thermal management and system cooling.

DARPA is asking industry suggest applications that VLPI photonic circuits could enable; the performance benefits of the VLPI circuits; how applications could reduce the need for electro-optical transducers; software algorithms that VLPI integrated circuits could enable; and design approaches that could mimic digital computing using optical computing.

DARPA also wants industry's opinions on limitations and new approaches in design automation for VLPI photonic circuits; the state-of the-art in today’s photonics design tools; limits on the maximum size of photonic circuit modeling; and photonic design algorithms and automation.

Companies interested were asked to email unclassified responses by 15 July 2025 to DARPA at [email protected]. Email questions or concerns to DARPA's Anna Tauke-Pedretti at [email protected]. More information is online at https://sam.gov/opp/0d91f604d4d54bd79881be8b9f9721be/view.