Entanglement in Atomic Resonance Fluorescence
P. Grünwald, W. Vogel · Physical Review Letters · 2010
The resonance fluorescence from regular atomic systems is shown to represent a continuous source of non-gaussian entangled radiation propagating in two different directions. For a single atom entanglement occurs under the same conditions as squeezing. For more atoms, the entanglement can be more robust against dephasing than squeezing, hence providing a useful continuous source for various applications of entangled radiation.