High-purity single photons obtained with moderate-NA optics from SiV center in nanodiamonds on a bullseye antenna

Abstract

Coherent exchange of single photons is at the heart of applied quantum optics. The negatively-charged silicon vacancy center in diamond is among most promising sources for coherent single photons. Its large Debye–Waller factor, short lifetime and extraordinary spectral stability is unique in the field of solid-state single photon sources. However, the excitation and detection of individual centers requires high numerical aperture (NA) optics which, combined with the need for cryogenic temperatures, puts technical overhead on experimental realizations. Here, we investigate a hybrid quantum photonics platform based on silicon-vacancy center in nanodiamonds and metallic bullseye antenna to realize a coherent single-photon resource that operates efficiently down to low NA optics with an inherent resistance to misalignment.

Room-Temperature Fiber-Coupled Single-Photon Sources based on Colloidal Quantum Dots and SiV Centers in Back-Excited Nanoantennas

“…For low NAs, the SiV-based device yielded lower directivity compared to both the simulation and the CQD device. We attribute this drop in directivity to the extended spatial distribution of the SiV centers within the nanodiamond, which is large compared to that of the nanodiamond employed in our previous work . It can be noted that there are small differences in the collection efficiency between the simulation and the experiment.…”

“…Typically, ,,,− measurements are done in a front excitation configuration, where the optical path of the laser excitation coincides with that of the emission collection. In that case, the same objective is used for both excitation and collection of photons from the quantum emitter.…”

Hybrid Quantum Nanophotonics: Interfacing Color Center in Nanodiamonds with Si3N4-Photonics

“…When coupled to nanopatch antennas the emission rate of single NV center can be enhanced into an ultrabright regime with a sub-nanosecond emission [12]. NV [22] and silicon-vacancy (SiV) [23] center in NDs were placed in the center of bullseye antennas achieving a high-purity single photon source and enabling access via moderate-NA optics. An essential improvement towards an efficient integration of color centers in NDs into photonics is the usage of nanopockets.…”

Bullseye dielectric cavities for photon collection from a surface-mounted quantum-light-emitter

“…To date, reported bullseye structures are mainly dielectric-based and lossless, a key advantage over plasmonic cavities, which include absorptive metals in the high-field region 7 , 15 , 16 . These advantages have led bullseyes to be used to enhance the performance of quantum dots 8 , defect centres in diamond 17 , 18 , and in two dimensional (2D) materials 11 , 19 . Predicted values for spontaneous emission rate enhancement in the literature for the bullseye structures are as high as 56 20 .…”