What if the next leap in “Wi-Fi-like” speed doesn’t come from better antennas, but from light itself? A UK-led research team has demonstrated a chip-scale optical wireless system that pushes data through the air at an eye-catching 362.7 gigabits per second, using tiny lasers instead of radio waves.
That speed headline is fun, but the more interesting detail is the energy angle. The researchers measured about 1.4 nanojoules per bit, which they describe as roughly half the energy per bit of leading Wi-Fi under comparable conditions, at least in this lab setup.
In a world where digital infrastructure already carries a real climate footprint, efficiency gains like that can add up, even if they arrive one room at a time.
What researchers actually demonstrated
At the center of the prototype is a 5 × 5 array of vertical-cavity, surface-emitting lasers, or “VCSELs,” a type of efficient semiconductor laser commonly used in data centers and sensing. Each laser can be controlled separately, so it can carry its own stream of data at the same time as its neighbors.
In the reported tests, 21 of the 25 lasers were operating, with each channel pushing roughly 13 to 19 Gbps. Combined, those parallel channels reached 362.7 Gbps across a two-meter free-space optical link, which is about 6.6 feet.
The team also tackled a practical issue that shows up fast in optical wireless, which is interference when multiple beams overlap. They used microlenses and additional optics to shape the beams into a structured grid, reporting over 90% uniformity across the target area, and they demonstrated four simultaneous links delivering about 22 Gbps combined in a multiuser test.
The environmental angle behind the speed headline
It’s easy to treat faster wireless as a luxury, but the demand curve is not slowing down. According to the International Energy Agency, data transmission networks consumed about 260 to 360 terawatt-hours in 2022, roughly 1 to 1.5% of global electricity use, and data centers sit in a similar range.
This is where “energy per bit” starts to matter in everyday terms. When more video calls, streaming, cloud gaming, and connected devices pile into indoor networks, the cost shows up in hardware upgrades and, eventually, the electric bill.
Cutting the energy needed to move the same amount of data is not the whole climate solution, but it’s one of the levers the tech industry can actually pull.
There’s an important caveat, though, and it keeps the story honest. The reported 1.4 nJ per bit is a measurement from a controlled demonstration, not a complete “whole-building” energy audit, so real-world savings will depend on receivers, system design, and deployment choices.
Why light can help where radio struggles
Traditional Wi-Fi is fighting physics and crowding at the same time. The radio spectrum is finite, indoor interference is real, and dense spaces like offices, apartment buildings, airports, and conference venues can become a noisy RF soup that everyone has felt as buffering and dropouts.
Optical wireless changes the playing field because it uses light, not radio waves. In the researchers’ description, light offers much more available bandwidth, avoids interfering with existing Wi-Fi and cellular systems, and can be aimed more precisely at specific zones in a room.
That last part is key if you want multiple users without everyone stepping on everyone else.
Still, there’s no magic wand here. For the most part, optical links behave best with clear paths and careful alignment, and indoor environments are full of movement, occlusion, reflections, and “someone just walked between the transmitter and the receiver.”
Even broader reviews of optical wireless point out that many free-space optical approaches are fundamentally shaped by line-of-sight constraints.
Business implications from offices to data centers
From a business standpoint, the pitch is not “replace Wi-Fi.” It’s closer to building a fast, efficient “express lane” indoors where traffic is heaviest, then letting radio networks handle mobility and coverage the way they always have.
The SPIE release explicitly frames optical wireless as a complement that can offload crowded radio networks in indoor spaces.
If you manage a venue with hundreds or thousands of devices in one room, the idea is tempting. Think training floors using high-resolution AR, hospitals that care about RF interference management, or data centers and labs that want dense connectivity without adding to spectrum congestion.
And yes, the sustainability angle is part of the sales deck now, because energy efficiency is increasingly tied to procurement and reporting.
The hurdles look familiar for any deep-tech rollout. Scaling from a two-meter demonstration to real buildings means dealing with faster receivers, integration into fixtures like ceilings or access points, safety and compliance for laser-based systems, and the messy reality of installation costs.
In other words, the “green” win will depend on whether the product ends up simple enough to deploy widely.
Military and defense use cases and the caveats
Defense and security planners pay attention whenever communications can move off congested radio bands. Optical wireless can be highly directional, which can reduce spillover beyond a room and, in some scenarios, lower the risk of interception compared with omnidirectional RF systems.
It also sidesteps RF jamming in a narrow sense, since the link is not riding on the radio spectrum in the first place.
But the same limitations matter even more in military contexts. Smoke, dust, cluttered interiors, movement, and the need for reliable links under stress can punish line-of-sight systems, so optical links are more likely to show up as a layered option rather than a standalone replacement for radios.
That’s why the researchers themselves emphasize complementing existing wireless networks, not declaring a funeral for Wi-Fi.
The most realistic near-term defense value might be in controlled indoor environments where RF is restricted or crowded, and where energy efficiency and electromagnetic compatibility actually matter.
The study was published on Advanced Photonics Nexus.
