  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.
