An Interface between light and matter for Quantum Networks
Friday, May 25th, 2012 by Antonio ManzaliniPhysicists, involved in Quantum Networks developments, are looking for ways to transfer quantum information between matter and light using entanglement, a property in which the state of one particle depends on the state of a second ones.
At the University of Innsbruck they have developed and tested a prototype of interface between light and matter for future quantum processing and networking.
The experimental device traps a single calcium ion in a Paul trap and places it between two highly mirrors. The ion is excited with a laser, thus generating a photon entangled with the ion and reflected back and forth by the mirrors. Interestingly, the frequency and amplitude of the laser can be tuned so that the target collective state of the ion and photon is reached.
Experimental apparatus
“Whenever we have to transfer quantum information from processing sites to communication channels, and vice versa, we’re going to need an interface between light and matter” explains the Physicists.
The experiment is impressive as it offers important practical insights into the interaction of light and matter: another step towards quantum computers or future quantum networks.
Ref.: A. Stute, B. Casabone, P. Schindler, T. Monz, P. O. Schmidt, B. Brandstätter, T. E. Northup, R. Blatt, Tunable Ion-Photon Entanglement in an Optical Cavity, Nature, 2012, DOI: 10.1038/nature11120
May 25th, 2012 at 11:40 am
The whole field of quantum communications is evolving. Most recently first the Japanese and then a European team managed to “teleport” information via quantum entanglement. Per se it is not something that can be applied in practice but it is a further step in “understanding” the viability of entanglement to code information.
This may come handy once classical cryptographic method based on factorization will no longer be usable. Entanglement may be the answer to sustain a world where economical transactions are on line. That will also require end to end optical networks and specific network architectures. This is something that may find application in the next decade but next decade optical networks are being deployed today and though this decade. Better make them right now.