Quantum Time Transfer (QTT)
A patented timing method that uses quantum optical links between satellites, ground sites and fiber to synchronize clocks to under a nanosecond, planned as a global time service that does not depend on GPS.
Why it matters
Telecom networks, data centers, power grids and stock exchanges commonly take their time from GPS, whose signals are weak and easy to jam or fake. A separate time source that Xairos says is about 1,000 times more accurate and harder to tamper with would protect that infrastructure.
How the technology works
Xairos's Quantum Time Transfer protocol combines quantum hardware, very precise clocks and optical communications to compare clocks at two ends of a link with sub-nanosecond accuracy. The company describes its goal as a global entanglement grid over space and fiber.
In May 2026 it ran simultaneous quantum and optical links through its Ares terminal over a 2 km free-space range; the finished terminal is meant to add 10 Gbps optical communications.
Sources
Updated Oct 22, 2026 · How we source facts · Suggest a correction