Novel hollow-core optical fiber transmits data faster with record low loss
21 comments
·September 3, 2025GistNoesis
davidkuennen
This is actually much more important than the volume of data transferred. Having 33% lower latencies across the globe would be huge.
Sesse__
It's true, but for most cases, the volume of a fiber is not the problem anyway. Latency is a problem most of us somehow bump into every day, while most fibers in the ground are nowhere near what you can push out of DWDM (e.g., off-the-shelf equipment will easily allow you to run 20x100Gbit over a single fibre, but many of them only carry a single 10Gbit or even 1Gbit link).
Trans-continental is different, because you'll need amplifiers. Many, many amplifiers in a row. And those generally work well only in a fairly limited band. But unless you're doing submarine, bandwidth is almost never the problem.
To make things worse, a lot of existing medium-haul fiber links are actually twice as long as you'd expect, due to the desire to cancel out dispersion; you first run the fiber e.g. 10km from place to place, and then run it through a large 10km spool (of a slightly different type of fiber) in the datacenter to cancel out the dispersion. This is slowly going away, but only slowly.
xeonmc
does using hollow core means you can do away with dispersion compensation?
Sesse__
AFAIK yes, but if that's your goal, a far easier solution is to just use transmission standards that don't care about dispersion (coherent detection). E.g., all 100gig transmission already does not care about it.
Joel_Mckay
Sounds like it was something like CML for >200km runs. =3
PetitPrince
Thanks for your precision. Off-topic: It's true that "faster Internet" means "bigger Internet" in common language, just like in photography "faster lens" means "lens with more light gathering capability". I wonder if there's other field where "faster" is misused.
hyperhello
So submarine cables were limited to 0.67c and now aren’t? Can this really work?
p_j_w
> So submarine cables were limited to 0.67c and now aren’t?
I think it’s more like in the future they might not be. It’s anyone’s guess how mass production and deployment of this might look.
b3orn
For submarine cables there are two things here. The first is lower attenuation which allows for fewer amplifiers along the route making it overall cheaper. The second is lower latency. There have been cases where high frequency trading people went wireless to get lower latency because of the higher propagation speed of EM-waves in air. For really long distances you can go theoretically use satellite links to get lower latency than a submarine cable even if the total distance increases.
Figs
Someday, someone is finally going to work out how to do comms with neutrinos (which can pass directly through the Earth and come out the other side) and make so much money...
chasil
Interesting quotes from the article:
"There has not been a significant improvement in the minimum attenuation—a measure of the loss of optical power per kilometer traveled—of optical fibers in around 40 years...
"The new design maintains low losses of around 0.2 dB/km over a 66 THz bandwidth and boasts 45% faster transmission speeds...
"The new fiber is a kind of nested antiresonant nodeless hollow core fiber (DNANF) with a core of air surrounded by a meticulously engineered glass microstructure.
"The team believes that further research can reduce losses even more, possibly down to 0.01 dB/km, and also help to tune the fiber for low-loss operation at different wavelengths. Even the losses achieved, however, open up the potential for longer unamplified spans in undersea and terrestrial cables and high-power laser delivery and sensing applications, among others."
Sesse__
> "The new design maintains low losses of around 0.2 dB/km over a 66 THz bandwidth and boasts 45% faster transmission speeds...
0.2 dB/km is already a pretty common loss ratio, though. It's true that you won't get that over the entire 1310–1550nm range (the ~35 THz range commonly in use), but you generally can't use all of that for long-haul links anyway due to the way repeaters work.
More interestingly, they promise 0.06 dB/km or so in the most relevant bands. If they can keep that up, it would mean less need for amplifiers, which is a Good Thing(TM).
PaulKeeble
I really didn't see this coming. After 40 years of fibre I just thought we should roll this out across the globe as the solution to every home and we had data transmission solved and likely wouldn't need an upgrade until we found something substantially better, maybe quantum entanglement communication. Turns out it was improvable and now the insane amounts of fibre we have already deployed is now obsolete.
mschild
The currently installed fibre cables work just as well as they did a year ago. Calling them obsolete is a bit of stretch.
Besides, I think most homes are not even close to using the full capability of what fibre can offer nor do a lot of people need that extra bit of speed to browse Instagram/Facebook/YouTube/Whatever else.
nmstoker
UK, so what's the betting no one got a patent on this?!
bragr
How does one splice a cable with such a complex geometry? Is that a solved problem already?
nicholasbraker
You probbaly need a specialised crew to do this and as such such fiber won't be installed in your own neighbourhood for your Fiber-to-the-Home connection anytime soon I guess. But, maybe in a few decades it will.
When such technology becomes practical for the large telco's it will be implemented soon as this saves on attenuation equipment.
aaron695
[dead]
Note here that "faster" here really means more speed and not an increase in the volume of data transferred : The light go through the air hollow-core so can go at near "c" (the speed of light in vacuum) speed, instead of being constrained to "speed of light in glass which is only "2/3 c". This allows reduce latency for long distance communication.
https://spie.org/news/photonics-focus/julyaug-2022/speeding-...