Data center interconnect design and manufacturing startup OpenLight Photonics Inc. says it wants to accelerate the transition to silicon photonics after spinning out of its parent company Synopsys Inc. and closing on $34 million in Series A funding.

Today’s round was co-led by Xora Innovation and Capricorn Investment Group and saw participation from Juniper Networks, which is now a part of Hewlett Packard Enterprise Co., Mayfield, Lam Capital, New Legacy Ventures and K2 Access.

OpenLight has ambitions to become a key player in the design and manufacture of silicon photonics, which are a new kind of data center interconnect that’s used to link clusters of thousands of graphics processing units and other kinds of chips to power artificial intelligence and high-performance computing workloads.

Silicon photonics can solve a pressing bottleneck, where the processing capabilities of AI are no longer held back by computational limitations, but instead connectivity. The most advanced AI models today are powered by enormous clusters of GPUs, and this requires an ability for them to communicate with one another quickly. But they cannot keep up, and so this is where the new bottleneck exists. According to a study last year by Xscape Photonics, most AI developers can use only about 25% of a GPUs’ capacity because of the networking limitations they face.

The problem is that most existing data centers rely on electronic interconnects, but these lack the throughput to keep up with the most powerful processors in use today. As a result, GPUs often sit idle, waiting on a message from other processors before they can move onto the next computation, slowing down AI responses. Silicon photonics ditch the electronic signals and instead rely on the manipulation of light to transmit data from chip to chip at much greater speeds.

Accelerating silicon photonics

OpenLight designs and builds what it calls photonic application-specific integrated circuits or PASICs that power these new optical interconnects. PASICs can be thought of as the photonic equivalent of application-specific integrated circuits or ASICs, which are central to the operation of most electrical devices and computers today, optimizing performance, cost and efficiency. OpenLight believes its PASICs will become a core enabler of next-generation data center interconnects, but they can also be used in other applications, such as telecommunications, automotive and industrial sensing and quantum computing.

Chief Executive Adam Carter told SiliconANGLE that PASICs can help to make existing photonics-based interconnects much faster than is currently possible.

“Traditional silicon photonics hits performance ceilings at around 200 Gbps per waveguide, but OpenLight’s heterogeneous integration, particularly with indium phosphide, allows for high-performance 200G and 400 G modulators to be built directly into the chip,” he explained. “This enables dense, scalable optical interconnects with lower power consumption and higher bandwidth, which is key for AI workloads.”

The startup is focused on designing and building PASICs, and offers three distinct services, Carter said, including design, where it works with customers to create customized PASICs based on their specific use case requirements. It also supports design enablement with its Process Design Kit or PDK, enabling customers to design their own PASICs. OpenLight’s PDK is based on the heterogeneous integration of indium phosphide and silicon photonics, and provides access to an extensive library of active and passive components that span integrated lasers, amplifiers, modulators and detectors.

Once the designs are ready, OpenLight can then manufacture the physical PASICs for customers in partnership with Tower Semiconductor Inc., which has already validated its PDK to ensure each design is production ready. In other words, the startup allows customers to quickly design and build PASICs using proven building blocks, accelerating time-to-market.

Carter explained that being able to customize its PASICs is a key differentiator and a strong advantage, because each customer and application has very particular requirements when it comes to the individual components, such as the laser, modulator and semiconductor amplifiers used.

“OpenLight doesn’t build one-size-fits-all chips. Instead, we provide a robust, production-ready PDK and a library of silicon and indium phosphide components that allow customers to design their own PASICs, tailored to their specific applications,” Carter said. “Our customers aren’t buying just chips; they’re establishing a toolkit and the flexibility to build their own. This agility is especially important in a rapidly evolving market where standards are still forming, such as CPO, and allows customers to innovate and differentiate more quickly than with off-the-shelf solutions.”

Carter said OpenLight’s customers span include semiconductor companies, network equipment manufacturers, systems integrators and hyperscale data center operators. “We also support customers in adjacent markets like lidar, high-speed computing, industrial sensing and quantum computing,” he said. “Our first customers will start production at the end of 2025, generating the first royalty revenue for OpenLight in 2026. It is expected that announcements will be made as that happens.”

Long-term ambitions

The early-stage funding round comes just weeks after OpenLight completed its transition from a subsidiary of the chip design firm Synopsys to a standalone company, and it says it’s now ready to address the growing demand for faster and more efficient data movement in AI data centers. Carter said it’s not just the funding that’s useful for OpenLight, but also its investor’s expertise. He pointed out they have deep roots in the semiconductor industry, and that these contacts will help it to create a viable ecosystem around its technology.

“This funding will allow us to scale our operations, deepen our R&D efforts, and bring our groundbreaking products to market faster,” he said. “We believe heterogenous integrated silicon photonics will transform the way data is processed and transmitted, and we’re excited to be at the forefront of this revolution.”

Among other things, OpenLight intends to expand the number of active and passive components in its PDK library, with plans to offer customers a faster 400 gigabyte-per-second modulator and more advanced on-chip laser technology. Carter said the goal is to provide customers with the most flexible component design library in the industry. At the same time, he has plans to scale the company’s team to support early adopters as they move to high volume production of PASICs.

Capricorn Managing Partner Dipender Saluja expressed confidence that the rapid adoption of optical interconnects is inevitable due to the increasing data demands of AI Models and the persistent desire to reduce infrastructure costs.

“OpenLight’s heterogeneous architecture delivers on all three axes – performance, reliability and cost – which have hitherto held back the ubiquitous adoption of optical interconnects,” he said. “The strong foundry relationships and PDKs that OpenLight has developed create an ideal opportunity to meet the scale of demand that is needed for next generation AI hardware.”

Photo: OpenLight