Record 100,000 Entangled Photons Detected
Record 100,000 Entangled Photons Detected - Physics-Math - 30 October 2012
A whopping 100,000 entangled photons have been detected for the first time, beating the previous record of just 12. The technique for spotting this delicate quantum link among so many photons could prove useful for safely sharing keys used in encrypted communications.
Entangled photons have linked quantum states, such that measuring the state of one photon determines the state of the others, no matter how far apart they are.
Detecting entanglement usually involves coincidence measurement - the simultaneous detection of multiple photons in the same quantum state at different locations. This method has so far worked for up to 12 photons. Although it is possible more photons have been entangled in previous experiments, the detectors are not sensitive enough to sort out entangled from non-entangled particles when a large number of photons are involved.
“When you go to high numbers you need a completely different technique,” says Maria Chekhova of the Max Planck Institute for the Science of Light in Erlangen, Germany.