Resonant dielectric waveguide-based nanostructure for efficient interaction with color centers in nanodiamonds

Diamond nanoparticles containing single color centers are considered to be one of the most promising realizations of the sources of single pho- tons required for many potential applications in quantum telecommunication and quantum computing systems. Their implementation in practical schemes, however, requires a sufficient increase in their brightness, including the enhancement of both emission and collection efficiency. In this work, we propose a design of a compact planar structure composed of a dielectric periodic cavity coupled with a strip waveguide that is particularly suitable for improving optical characteristics of color centers embedded in a nanodiamond placed inside the structure. We numerically demonstrate that such scheme permits the achievement of simultaneous increase of emission rate of color centers by $\approx 50$ times in a spectral range $\approx 2$ nm, and up to $\approx 85\%$ out-coupling efficiency of emission to the dielectric strip waveguides. We analyze the main factors that decrease the performance of the proposed arrangement and discuss the possible ways for restoring it.