  Engineering the directionality and emission rate of quantum light sources is
essential in the development of modern quantum applications.In this work we use
numerical calculations to optimize the brightness of a broadband quantum
emitter positioned in a hybrid metal-dielectric circular periodic nanoantenna.
The optimized structure features a photon collection efficiency of 74% (82%)
and a photon flux enhancement of over 10 (6) into a numerical aperature of 0.22
(0.50) respectively, corresponding to a direct coupling into two types of
multimode fibers. In order to enhance the emission rate, we present a new
circular nanoantenna design where a quantum emitter is attached to a silver
nanocone at the center of the antenna. After optimization, we find a collection
efficiency of 61% (78%) into a numerical aperature of 0.22 (0.50), giving a
brightness enhancement of 1000 (600) for an unpolarized emitter. The
enhancements in both structures are broadband due to the low quality factor of
the device and are therefore ideal for room-temperature sources. This type of a
scalable design can be utilized towards on-chip, high brightness quantum light
sources operating at room temperature.
