  Fabrication of single nickel-nitrogen (NE8) defect centers in diamond by
chemical vapor deposition is demonstrated. Under continuous-wave 745 nm laser
excitation single defects were induced to emit single photon pulses at 797 nm
with a linewidth of 1.5 nm at room temperature. Photon antibunching of single
centers was demonstrated using a Hanbury-Brown and Twiss interferometer.
Confocal images revealed approximately 10^6 optically active sites/cm^2 in the
synthesized films. The fabrication of an NE8 based single photon source in
synthetic diamond is important for fiber based quantum cryptography. It can
also be used as an ideal point-like source for near-field optical microscopy.
