Tangled Photons & Encryption
Developed by researchers at Toshiba Research Europe and at Cambridge University, the quantum device has many possible uses in communication, quantum computing, medical imaging, and chip design. But its most immediate use will be in the transmission of encryption keys.
"With pairs of entangled photons," explains Rupert Goodwins of ZD Net UK, "the state of one can be deduced by measuring the state of the other. Combining this with statistical techniques, it's possible to send encryption keys to a remote location and to be sure they haven't been intercepted."
Here's a slightly more elaborate description, from the Austrian site, Quantenkryptographie: "In contrast to existing classical schemes of Key Distribution, Quantum Key Distribution does not invoke the transport of the key, since it is created at the sender and receiver site immediately. Furthermore, the key is created from a completely random sequence, which is in general an extremely difficult task in classical schemes. Finally, eavesdropping is easily detected due to the fragile nature of the qubits invoked for the quantum key distribution."
Clear enough for you? At the highest level, this is a significant step forward in the science of quantum computing and the development of optical networks.
— Richard Martin, Senior Editor, Unstrung