One-step integration of metal nanoparticle in photonic crystal nanobeam cavity

A single step process of integrating a resonantly tuned silver nanoparticle into photonic crystal nanobeam cavities fabricated by focused ion beam milling is presented. Even though the quality factor of the cavities is reduced by a factor of 20, the emission peak at the cavity resonance is enhanced by 5-fold with respect to the cavities without the metal nanoparticle. The fluorescence is also compared before and after etching away the nanoparticle. Experimental quality factors and wavelength shifts are found to agree reasonably well with simulation values. These results are promising for future single photon emission studies involving the incorporation of quantum dot or NV center emitters into hybrid plasmonic/photonic crystal cavities for enhanced emission rates while retaining reasonably high quality factors.