|MadSci Network: Physics|
Henry, Thanks for the question. I think you were reading about an experiment that created a material called a Bose-Einstein condensate. This can only exist at very low temperatures, and the laser beams are used in a special way to cool the condensate. The condesate has the properties of slowing down light tremendously and also not absorbing the light. One place you can read about this is at:
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