Photonic molecule
Photonic molecules are a synthetic form of matter in which photons bind together to form "molecules". According to Mikhail Lukin, individual (massless) photons "interact with each other so strongly that they act as though they have mass". The effect is analogous to refraction. The light enters another medium, transferring part of its energy to the medium. Inside the medium, it exists as coupled light and matter, but it exits as light. Researchers drew analogies between the phenomenon and the fictional "ligh...
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