Ultra compact hybrid plasmonic–photonic coupler: configuration of metal–silica–silicon

Abstract

In this work, a novel and practical configuration as a hybrid plasmonic–photonic coupler based on silicon (Si) nanofibers, silica waveguides and metal nanoparticles is examined and investigated. All of utilized waveguides, fibers and nanoparticles are embedded in an \(\hbox {Mg}_{2}\hbox {F}\) crystal host. Integrated plasmonic–photonic coupler provides significant transmission efficiency during guiding and propagating of light. Utilizing enhanced plasmonic waveguides helps to reduce the inherent losses such as scattering into the far-field and absorption of optical power inside the employed components, especially in nanoparticles. The transmission loss component under transverse electric excitation (TE) for the superstructure has been calculated as approximately \(\gamma _{T}=3\,\hbox {dB}/675\) nm. Also, we investigate the coupling efficiency at overlapping regions between Si nanofibers and silica (\(\hbox {SiO}_{2})\) waveguides which is referred to near-field interactions. Transmitted power ratio and the group velocity of the propagated light are computed and depicted for the proposed coupler.