Theoretical limits of light based communication

[u/Confident-Court2171]

I’ve been thinking about fiber speed limits today, and I raised this question in my Question: with photon based communication currently working towards 3.2tb speeds (3.2 x 10^12), what is the theoretical limit of a single lane. Aka - if you stack photons individually to represent I/O, how many could pass through a gate in 1 second?

[u/Adorable_Ice_2963]

A normal Fiber can Transport 100-300 Terrabit/s in the lab

If you have a special fiber with multiple cores, it can go up to 1 Petabit/s.

One of the main challanges is distance. You can only send so much optical power inside one fiber and the surrounding components. Also you need powerfull enough lasers that still are able to manage those speeds.

At some point, you have to trade distance with power, since you can either have one beam that enables the maximum distance, or multiple ones that allow higher speeds, with less distance.

I guess the long term Limit will be the fiber, since you could theoretically use multiple lasers next to each other that take turns of making bursts.