Dual-channel broadband slow surface plasmon polaritons in metal gap waveguide superlattices

摘要

We propose and demonstrate a kind of low-loss plasmonic superlattice with a few coupled resonant cavities to realize dual-channel broadband slow surface plasmon polaritons (SPPs) around two telecom wavelengths of 1550 nm and 1310 nm. The dual-channel slow SPPs result from the introduction of two kinds of coupled cavities into the superlattices. Theoretical analysis is confirmed by the finite-difference time domain (FDTD) numerical simulations. Our structures offer another avenue for researchers to explore novel slow SPP technologies and thereby may inspire further exploration of advanced photonic devices for next-generation telecommunication, optical data processing, and on-chip integration.