Applications
Quantum Repeater
A proposed device for extending entanglement distribution over long distances, essential infrastructure for a future quantum internet.
Definition
A quantum repeater is a device designed to extend the range over which entanglement can be reliably distributed, addressing the problem that entangled photons sent through fiber optic cables gradually lose fidelity over distance, similplaying a role analogous to repeaters in classical telecommunications.
Technical Definition
Quantum repeaters typically work by dividing a long distance into shorter segments, establishing entanglement across each segment, then using a technique called entanglement swapping to link the segments together into one long-distance entangled connection — all without ever directly measuring (and destroying) the underlying quantum information.
Visual Explanation: An Analogy
Think of a quantum repeater like a relay race, where instead of one runner trying to carry a fragile object the entire distance (which would likely break it), multiple runners each carry it a short distance and carefully pass it on.
Real-World Use Cases
- Identified as the key missing technology needed for a large-scale quantum internet
- Early prototypes have been demonstrated extending entanglement distribution over standard telecom fiber