Experimental Bell Inequality Violation with an Atom and a Photon
  We report the measurement of a Bell inequality violation with a single atom and a single photon prepared in a probabilistic entangled state. This is the first demonstration of such a violation with particles of different species. The entanglement characterization of this hybrid system may also be useful in quantum information applications. 
D. L. Moehring, M. J. Madsen, B. B. Blinov, C. Monroe