Copper carries data by moving electrons, and electrons generate heat and lose signal strength as frequency and distance increase. Silicon photonics carries the same data by moving photons instead, and photons neither generate heat nor incur signal loss.
That difference is why data centres and telecom networks are rebuilding their highest-bandwidth links around light.
The Growing Bandwidth Challenge Facing Modern Communication Networks
AI training and inference workloads move data between processors and servers continuously, not in short bursts. Cloud computing platforms and the wider growth of internet traffic layer on top of that.
As a result, communication infrastructure across data centres and telecom networks must now meet constant demand for high bandwidth. In the past, such peaks were one-time events. Now, they are the baseline.
The current data centre infrastructure is ill-equipped for this demand profile. Existing networking technologies were built around lower, more variable data rates. Pushed to sustained high-bandwidth operation, they hit limits in energy consumption, physical reach, and signal quality well before meeting demand. That mismatch between what modern workloads demand and what electrical interconnects can sustain makes bandwidth a central consideration in both data centre and telecom network design.
Why Electrical Interconnects Are No Longer Enough
Copper interconnects move data by driving current through a conductor, and every property that makes that reliable at moderate data rates works against it at high ones.
- Bandwidth ceiling: electrical signalling has a practical limit on how many bits per second a single channel can carry before the signal becomes too noisy to read reliably.
- Power consumption climbs with distance: driving a signal farther, or faster, requires more current, and that current dissipates as heat rather than useful work.
- Heat compounds at rack scale: a data centre with thousands of links generates a thermal load that has to be actively managed, which costs more and adds design complexity.
- Signal degrades over distance: attenuation and crosstalk both worsen as frequency increases, so the reach of a viable copper link shortens as demand for higher data rates grows.
These are not new problems. What has changed is the scale at which they occur. A single rack-to-rack link tolerating some loss is manageable. Thousands of links, each pushed toward its bandwidth ceiling at once, are a system-level constraint that copper is unable to handle.
Why Silicon Photonics Is Becoming the Preferred Solution
Silicon photonics addresses this by moving data as light rather than electrical current, using photonic components fabricated on the same silicon platforms and largely the same CMOS-compatible processes that semiconductor manufacturing already relies on.
Light does not generate resistive heat the way current does, and an optical signal does not degrade over distance in the same way an electrical one does. The result is a link that carries more data over longer distances while using less power than the equivalent electrical connection.
Also, this technology builds on existing wafer fabrication infrastructure. Rather than requiring an entirely new manufacturing base, prototypes can be tested and rolled out at volume faster than designing from scratch.
How Silicon Photonics Is Powering AI Data Centres
AI training runs across GPU clusters that constantly exchange data between accelerators, at data rates that push electrical interconnects to their limits within a single hardware generation. Communication thresholds across permutations from GPU-to-GPU to rack-to-rack also constrain system performance.
Optical interconnects raise that ceiling. They carry the same GPU-to-GPU and rack-to-rack traffic at higher bandwidth and lower energy cost per bit, without the heat load that limits how densely electrical links can be packed. For hyperscale operators, that translates directly into rack density: more compute per square metre of data centre floor, without a proportional increase in cooling and power infrastructure.
The Expanding Role of Silicon Photonics in Telecommunications
Silicon photonics also has applications in telecommunications, an industry that faces many of the same problems. Metro networks and long-haul optical links carry most of their long-distance data traffic on optical fibre. However, the electronics at each end, which convert electrical signals to light and back, are steadily reaching their limits.
Silicon photonics addresses that bottleneck by integrating more optical functions into fewer, smaller components, lowering the cost and power consumption of each transceiver without reducing the bandwidth it carries. That matters most where transceiver count scales fastest: in the 5G of today, and in the denser 6G network architectures of the future. Silicon photonics enables transceivers at the edge of the network to keep pace with the fibre at its core.
Building Scalable Optical Communication Systems
Silicon photonics rarely operates as a single component. It is usually one layer in a broader integration strategy that includes photonic integrated circuits (PICs), co-packaged optics (CPO), and heterogeneous integration of multiple material systems on a single platform.
- PICs: consolidate the modulators, waveguides, and photodetectors a system needs onto one chip, in the same way an electronic integrated circuit consolidates transistors.
- CPO: moves that photonic function physically closer to the switch or accelerator it serves, shortening the electrical path between the two and cutting the energy lost along the way.
- Heterogeneous integration: extends the platform further, bringing in materials such as indium phosphide for light generation where silicon itself cannot do the job efficiently.
None of these technologies replaces the others. Each addresses a different point in the same system, and together they make an optical network scalable, not just fast in isolated links.
NSTIC’s Role in Advancing Optical Communications
National Semiconductor Translation and Innovation Centre (NSTIC) supports this translation from research to deployable technology directly. Our 300mm wafer cleanroom processes both 8-inch and 12-inch wafers using a CMOS-compatible toolset, which means silicon photonics devices developed here can move from prototype to small-volume manufacturing without switching fabrication platforms partway through.
We work with photonics and optics companies, hyperscale and cloud infrastructure teams through contract research, joint collaboration, and cleanroom fabrication services. Our scope covers everything from a single process run to full device fabrication. For partners ready to deploy at scale, infrastructure determines whether the design becomes a shippable product or remains a demonstration.
The Future of Optical Networking
The bandwidth constraint is not going away; in fact, it will only grow more pressing as demands increase. AI workloads will keep compounding the volume of data moving between processors, and telecom networks will keep extending the reach and density of the traffic they carry. While electrical interconnects can continue to serve applications where distance and data rate stay within their limits, the links now defining data centre and telecom performance have already reached that ceiling.
Silicon photonics, alongside photonic integrated circuits, co-packaged optics, and heterogeneous integration, is what keeps that ceiling from becoming a hard stop. As these technologies mature together on manufacturable, CMOS-compatible platforms, the path from a working photonic chip to a network built on light gets shorter, not longer.