Experimental Realization of a Three-Qubit Entangled W State
Manfred Eibl, Nikolai Kiesel, Mohamed Bourennane, Christian Kurtsiefer, Harald Weinfurter · Physical Review Letters · 2004
We report on the experimental observation of the three-photon polarization-entangled W state using spontaneous parametric down-conversion. This state is inequivalent to the Greenberger-Horne-Zeilinger state under stochastic local operations and classical communications and thus is the representative of the second class of genuine tripartite entanglement. We study the characteristic features of entanglement and demonstrate the high degree of two-photon entanglement in the W state.