Stopping Light and Restarting it Again!

Dr. Lene Hau, Mallinckrodt professor of physics and applied physics at Harvard University, and her co-researchers, Dr. Naomi S. Ginsberg and Dr. Sean R. Garner, stopped and extinguished a light pulse in a tiny, supercooled sodium cloud called a Bose Einstein Condensate, and then brought the light pulse back into existence in another atom cloud in a separate location.

The information inside the light pulse was transferred from the first to the second cloud by converting the light pulse into a travelling matter wave, a small atom pulse that was a perfect matter copy of the extinguished light pulse. After the matter wave entered the second cloud, the atoms there worked together to restore the original light pulse.

Currently, scientists and engineers working in optical networks and quantum cryptography are only able to store an optical signal, but Hau’s work will enable them to have a greater degree of control over quantum processing than ever before.
Watch the video to see how it was done!