Nothing goes faster than light... usually!
In our laboratory we have used ultra-cold atom clouds to slow light pulses to the speed of a bicycle, which is 50 million times lower than the light speed in vacuum. In the process, a light pulse spatially compresses by the same large factor, from 1 km to only 0.02 mm, and the pulse can then be completely stopped and later restarted.From here, we have taken matters further: Stopped and extinguished a light pulse in one part of space and revived it in a completely different location. In the process, the light pulse is converted to a perfect matter copy that can be stored – 'put on the shelf' – sculpted, and then turned back to light. The storage time can be tens of seconds, and during this time, light could – under normal circumstances – travel back and forth to the Moon many times over. The experiments represent the ultimate degree of quantum control over light and matter, and in the talk I will describe how we manipulate light to this extreme.