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by osamagirl69 54 days ago
Would you care to explain how the NICT guys achieved 402Tb/s through a single (50km long!) fiber back in 2024 then? It seems like another factor of two would easily be in reach if they could extend their setup into the visible.
1 comments
lefra 54 days ago
Fibers are not transparent enough in visible. I found about 10dB/km (to be compared with 0.2 dB/km around 1550nm) [0]. This means that after every km the light intensity is divided by 10, which is completely impractical for telecommunications.

[0] https://media.thorlabs.com/globalassets/family-pages/shareda...

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osamagirl69 54 days ago
That depends on the application, the standard for short range (<100m -- fine for most anything that doesn't leave your building) is already to use 800nm.
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