Experimental generation of multi-photon Fock states
  We experimentally demonstrate the generation of multi-photon Fock states with up to three photons in well-defined spatial-temporal modes synchronized with a classical clock. The states are characterized using quantum optical homodyne tomography to ensure mode selectivity. The three-photon Fock states are probabilistically generated by pulsed spontaneous parametric down conversion at a rate of one per second, enabling complete characterization in 12 hours. 
Merlin Cooper, Laura J. Wright, Christoph S\"oller, and Brian J. Smith
quant-ph