Mahatma Gandhi once said, "There is more to life than increasing its speed." Wise words, indeed, for us personally. They also hold true for data centers, but in a different way. While increasing the speed of data as it moves through hardware is always good business practice, an equally important business factor is reducing the power costs in data centers – especially at scale.

This is the data center's "forever dilemma": How to maintain and improve speed and efficiency yet maintain or lower costs. Whenever a data center can cut back on power consumption and increase throughput at the same time, administrators tend to look at that potential solution.  CFOs demand it.

Silicon photonics, the rendering of hardware, science and technology of light, may be the realistic answer to this increasing demand. With electrical connections in semiconductor systems hitting limits on data transfer speeds, attention has shifted to hardware photonics, which uses optical connections to move data. These processors integrate the optical connections on the chip instead of relying on optical plug-in components in computer racks, which increase data speeds by only a limited amount.

Photonics encompasses generating, guiding, manipulating, amplifying and detecting light. The most important business value it brings is its capability to provide high-speed data transfer with low-power consumption. This makes it an attractive option for data centers that require high-speed data transfer while keeping power consumption low; hyperscalers are generally first in line for these devices. Silicon photonics also can be used in telecommunication installations to provide high-speed data transfer over long distances.

The latest such processors – new in only the last few months – promise to provide significant advantages over traditional pluggable optics. Silicon photonics IT is highly automated and integrates with industry standard CMOS (complementary metal-oxide-semiconductor) processes, which can improve reliability, scalability and density of optical communications.

Leaders in this market are Intel ($79 billion in 2022 sales), IBM ($57B), Cisco Systems ($50B), STMicroelectronics ($12.6B),  Global Foundries ($6.6B), II-VI Inc., Macom, NeoPhotonics, Inphi and Rockley. Broadcom, Hamamatsu Photonics, Toshiba, Schott AG, and Sony Corp. are comparatively minor players.

Innovation is happening in this space. From Synopsys and Juniper Networks’ new silicon photonics venture OpenLight to Intel’s advancements in multiwavelength integrated photonics, silicon photonics is beginning to show its power in the data center. These photonic circuits not only offer the scale of semiconductor wafer-scale fabrication, they also enable advantages in new electronics applications that use the properties of light in computation, communication, sensing, and imaging. All this is going to become increasingly important to the delivery of heavier amounts of data and larger AI/ML applications that will become commonplace in Web3.

Broadcom, an aggressively growing company that bought CA Technologies and Symantec in recent years and will be adding VMware in a few months, is a company that has targeted this sector and is serious about staying in it long term.

"Broadcom has demonstrated that they can reduce power consumption of optics by about half," Vlad Kozlov, principal at industry analysis firm LightCounting, told SDxCentral. "That's a big deal. Cisco was running a complete switch which was actually two switches; one was fully populated with pluggable devices and one fully populated with core package optics; they demonstrated 22% lower power for that (optical)  switch. So they should be able to get to 25% to 30% power reduction for the whole switch. That's also a big deal."

It is indeed – especially at scale. In an era in which power costs are increasing at anywhere from 2% to 4% per year in some regions, it's important for enterprises to maintain as much control as possible over data center power usage.

What Broadcom has done under the hood of this new system in connecting optical and pluggable components is a significant technical advance in the switch business. At the international Optical Fiber Communication conference in San Diego on March 1, Broadcom showcased the world’s first Tomahawk 5-based 51.2T Bailly CPO prototype system and demonstrated a fully functional Tomahawk 4 based 25.6T Humboldt CPO system.

On March 15, the company announced that the Tomahawk 5 Ethernet switch/router chips are shipping in production volume – a mere seven months after initial samples were tested.

The following technical description of the company's currently available switch is aimed at developers and architects of these systems: "Our Tomahawk 4 based 25.6T Humboldt CPO system operates with 128 lanes of 100G DR connectivity emerging from the ASIC substrate from four 3.2Tb/s integrated optical engines," wrote Broadcom VP of Optical Systems Near Margalit in a recent blog post. "The full system operates with half the switch lanes escaping optically and the other half electrically.  Each optical engine uses only two pieces of silicon – a PIC and an EIC packaged together at wafer scale pitch matched to the SerDes bumps inside the Tomahawk 4.

"The system demonstrates optical interconnect power consumption of less than 7W per 800G, a more than a 50% improvement from traditional pluggable modules."

On a 24/7, 365-days-per-year basis, this can add up to significant cost savings for the data center owner.

Broadcom has indeed been an innovator in this sector, Kozlov said. "I don't think (Broadcom) necessarily increases the data rate or the speed, but it has a radically new approach for combining optics with Ethernet switches," Kozlov said. "Broadcom surprised the industry two years ago when they first announced their intention of committing themselves to delivering this product, but they've been on a very aggressive schedule for bringing prototypes to the market."

Off the top, hyperscale cloud-service providers will be most interested in using these chips in their data centers, but it will take a period of time for enterprises of various sizes to consider upgrading to them, Kozlov said.

"I'm not sure if enterprise benefits from it that much (at this time). Power consumption issues for them are not as critical. They tend to deploy optics gradually over time. So buying a fully populated (optical) switch is not something that they would be interested in yet. Pluggable solutions are probably going to be the best for the enterprise market for some time.

"It's (the Tomahawk Bailly chipset) a very different solution. It's going to take customers some time to gain confidence and qualify it."

Recent industry reports disagree on the potential growth and size of this market. According to Expert Market Research, the global silicon photonics market – being driven by a rising demand for optoelectronics – is expected to see robust growth in the forecast period of 2023-2028, growing at a staggering CAGR of 42.1%. The market, EMR said, is projected to reach $7.8 billion by 2027.

An alternative report by Market Research Future projects that the global silicon photonics market is expected to grow at a CAGR of 18.56% during the forecast period of 2023-2032.

Lastly,  ResearchAndMarkets.com claims that the global silicon photonics market size was valued at USD $1.3 billion in 2022 and is expected to expand at a CAGR of 29.96% during the next five years, reaching USD $6.4 billion by 2028.

Based on these reports, it's a no-brainer that there will continue to be significant growth in the silicon photonic market for several years to come.