The light induced interaction between atoms have been emphasized in early research It's now widely accepeted that back influence of atomic density modification on the light propagation can be neglected in free space So far, two approaches have been applied to enhance the back influence effect One approach is to Another approach is to increase the density put an atomic gas in a cavity Sn Threee statistics and quantum tlucnntns an i Collect ve Atom kernel L ase CARLI gennum epee ef a Hose- nstein condensate chapped to a quantized light tel Cavity Opto- Mechanics with a Bose-Einstein Condensate Ferdinand Brennecke, Stephan Ritter, Tobias Donner, and Tilman Eswlinger'The light induced interaction between atoms have been emphasized in early research. It’s now widely accepeted that back influence of atomic density modification on the light propagation can be neglected in free space! 2   n So far, two approaches have been applied to enhance the back influence effect. One approach is to increase the density Another approach is to put an atomic gas in a cavity