An accurately timed sequence of two control laser pulses (arrow on the left) can take the system to the weak coupling regime. The internal state of the atom looks at the light waves passing by almost without pitching: the atom is weakly responsive to the photons trapped in the cavity; these photons, indeed, cannot excite it because they do not match the energy difference between the two excited states. The light emitted from the cavity (arrow on the top right) behaves like a flux of particles.
Picture credit: Alessandro Ridolfo and Rocco Vilardi, Messina University.
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