Controlled coupling of a single-diamond nanocrystal to a photonic crystal cavity.

We demonstrate the controlled coupling of a single diamond nanocrystal to a planar photonic crystal double-heterostructure cavity. A dip-pen deposition method and subsequent manipulation with an atomic force microscope was used to precisely position the nanocrystal on top of the cavity. The optical properties of this combined system are investigated with regard to changes in the quality factor and resonance wavelength of the cavity mode as a function of the size and relative position of the diamond nanocrystal. These studies represent an important step toward well-controlled cavity-QED experiments with single-defect centers in diamond.