Data on the internet travels at the speed of light through fiber optics. In classical networks, delays aren't critical, but for quantum communication, perfect synchronization is essential: particles of light with encoded information must converge at the detector in the same instant. The problem is that, after traveling different routes, they get out of sync — like ingredients of a dish that finish cooking at different times and have to wait for each other.
A new optical buffer solves this problem like a kitchen warmer: it holds light pulses until they're all ready to be 'served.' The device forces light into a fiber optic loop, where it runs nearly 4 kilometers in 18 microseconds — and all at room temperature, with losses under 0.5 decibels (practically unnoticeable). This buffer can hold over 200 pulses at once and works across the entire operational spectrum of long-distance communication.
What's more, the buffer even preserves quantum entanglement — that spooky connection between particles experimentally confirmed by Alain Aspect. And without lasers, whose foundations were laid by Charles Townes, such photonics would be impossible. So a simple fiber optic loop, resembling a kitchen gadget, brings us closer to a global quantum internet.
Almost all intercontinental communication operates in the 1530–1565 nm range — the only one where fiber optic glass is so transparent that a signal can travel hundreds of kilometers without amplification.
The dream of a quantum internet sometimes evokes the fictional 'ansible' — a device for instant communication across galaxies, though in reality even it doesn't violate the speed of light limit.