Research at Bonn and Cologne Universities Opens BEC-based Applications for Quantum Computing

Light forks one way in a Bose-Einstein condensate

Excerpts and salient points ~

+  Researchers at the universities of Bonn and Cologne in Germany have developed a new way of splitting photon wavepackets that involves cooling them down to a Bose-Einstein condensate (BEC) in a double-ridge microresonator structure. This thermodynamic method differs from the usual optical beam-splitting techniques because it is irreversible, meaning that the original beam cannot be reconstructed. The BEC-based process might be extended in the future to make new optical sources for entangled and correlated light states for applications in quantum computing.

“Our technique is a new, energetically-driven way to prepare optical quantum states,” Weitz tells Physics World. “We have demonstrated how to irreversibly create coherently split light.” The method, which is detailed in Science, might be extended in the future to realize new optical sources for entangled and correlated states of light, he adds.

+  The researchers observed the light wavepacket splitting by using a camera to monitor the optical radiation transmitted through one of the cavity mirrors. They also monitored the coherence of the beamsplitting by recombining the light beam paths. In this way, they were able to observe interference fringes of the beams.

+  The researchers now plan to prepare photons in a periodic lattice potential and enhance effective photon interactions. In such a set-up, highly entangled many-body states can become the lowest energy state in the cavity. “We could directly populate these quantum states by cooling using our method and these states could be used in applications such as quantum information and communication,” Weitz says.

Source:  physicsworld,  Light forks one way in a Bose-Einstein condensate…

Content may have been edited for style and clarity.