Multipartite entangled light from driven microcavities
D. Pagel, Holger Fehske, Jan Sperling, W. Vogel · Physical Review A · 2013
The generation and the characterization of multipartite entangled light is an important and challenging task in quantum optics. In this paper the entanglement properties of the light emitted from a planar semiconductor microcavity are studied. The intracavity scattering dynamics leads to the emission of light that is described by a four-partite $W$ state. Its multipartite correlations are identified by using the method of entanglement witnesses. Entanglement conditions are derived, which are based on a general witness constructed from $W$ states. The results can be used to detect entanglement of light that propagates through lossy and even turbulent media.