Investigating Light-Matter Interactions Through the Coupling of Single Emitters to Bowtie Nanoantennas

Metallic nanoparticles, which confine light into very small volumes and greatly enhance fields, have many exceptional and tunable optical properties. Nanodimers known as bowtie nanoantennas are known to have strong field enhancements and confinement to the gap between the triangles. However, due to intrinsic ohmic losses, obtaining strong coupling between an emitter and the cavity remains an issue. In this study, to elucidate the effects of the nanometric positioning of the emitter, we employ super-resolution single-molecule fluorescence techniques to study the effects of detuning, polarization, orientation, nanometer gap size, and adhesion layer have on the fluorescence properties of the dye, as well as the trapping dynamics of the system. A clear set of optimal parameters has been found, aided by finite element simulations, hinting towards obtaining the maximal coupling for single emitters in this geometry.