The impact of nanoantennas on ring resonators’ performance

The performance of ring resonators, as any other optical device, has been analysed and it is the purpose of many recent studies, due to their multipurpose optic response. Ring resonators can work as filters, amplifiers, modulators, repeaters or multiplexers. Recently, optical sensors based on ring resonators are designed with high sensitivities for non-invasive diagnosis, both in vitro and in vivo. The inclusion of nanoantennas optical devices that concentrate and amplify the electromagnetic field could increase the optical ring devices sensitivity response. In this article, the inclusion of nanoantennas in the ring resonator performance is studied. For that purpose, a Finite Element Tool is used to perform 2D simulations. It is concluded that nanoantennas can improve the output ring resonators response, leading to more reliable results as the quality factor, the bandwidth and the extinction ratio. Moreover, the nanoantenna location in the devices gives more degrees of freedom to reach the desired responses, since it is also dependent on the nanoantennas’ structure.