Entanglement among bright light beams: Creation, structure, sudden death

The possibility to generate multipartite entanglement in the laboratory allows further investigations of the structure of quantum correlations among many parties. We employ the optical parametric oscillator to directly produce three entangled bright beams of light and study their properties. In this tripartite continuous system, we observe a mixture of behaviours common to discrete systems pertaining to both the GHZ and the W classes of tripartite entangled states.