Generating non-Gaussian states using collisions between Rydberg polaritons

We investigate theoretically the deterministic generation of quantum states with negative Wigner functions, by using giant nonlinearities due to collisional interactions between Rydberg polaritons. The state resulting from the polariton interactions may be transferred with high fidelity into a photonic state, which can be analyzed using homodyne detection followed by quantum tomography. Besides generating highly nonclassical states of the light, this method can also provide a very sensitive probe for the physics of the collisions involving Rydberg states.