Why do photons repel one another?
What makes you think that they repel one another?
This article has me confused lol.
It is theoretical...
I just do not understand how photons could repel one another if they are solid state.
The OP is talking about this paper: Andrew Greentree, Charles Tahan, J. Cole, L. C. L. Hollenberg, "Quantum phase transitions of light", Nature Physics 2, 856 - 861 (2006)
Arxiv preprint: http://arxiv.org/abs/cond-mat/0609050
From this point on, I'll shut up and observe.
I'm way ahead of you. I found that paper earlier. Beats me!
The two-level system (TLS) creates a non-linearity, causing an interaction between the photons (a repulsion).
By adding photons to a two-dimensional array of coupled optical cavities, each containing a single two-level atom in the photon-blockade regime, they form atom-photon `molecules' termed dressed states or polaritons.
The coupling between the atom and the photons leads to optical nonlinearities and an effective photon-photon repulsion.
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