Bound modes analysis of symmetric dielectric loaded surface plasmon-polariton waveguides.

A symmetric dielectric loaded surface plasmon polariton waveguide is proposed and numerically analyzed. The characteristics of the symmetric and asymmetric bound modes, including the effective mode indices, propagation lengths, mode sizes and mode shapes at telecom wavelength 1.55 microm are investigated in detail. The simulation results show that the sub-wavelength confinement (about1.45 microm ) and a long propagation (about 820 microm ) can be realized. Although the mode sizes are a bit larger than that of the dielectric loaded surface plasmon polariton waveguide, an order longer propagation length can be achieved. The proposed symmetric dielectric loaded surface plasmon polariton waveguide provides a potential for low loss and high density photonic integration.