Delicate entanglement between photon pairs preserved over long distance
ZAMG/Mathias Stampfl/Wikimedia Commons
Communications of the future may be securely encoded in light that is twisted like fusilli pasta.
A long-distance transmission of particles of light above the Vienna skyline demonstrates a new way of relaying information using the tricks of quantum physics. Austrian researchers exploited the twistiness of light to establish a delicate quantum connection called entanglement between pairs of photons. The entanglement remained intact even after one photon from each pair traversed three kilometers.
The successful optical link, described online July 23 at arXiv.org, suggests that twisted light may play a key role in implementing quantum communication systems, which require preserving entanglement over great distances. “It allows you to pack more information into your transmission,” says Roger Andrews, a physicist at the University of the West Indies in St. Augustine, Trinidad and Tobago.