Long range surface plasmon polariton waveguides at 1.31 and 1.55 mu m wavelengths

Abstract

We investigate characteristics of gold metal strip waveguides based on long range surface plasmon polaritons (LRSPPs) along thin metal strips embedded in a polymer for practical applications at the telecommunication wavelengths of 1.31 and 1.55 mu m. Guiding properties of the gold strip waveguides are theoretically and experimentally evaluated with the limited thickness and width up to similar to 20 nm and similar to 10 mu m, respectively. The lowest propagation loss of similar to 1.4 dB/cm is obtained with a 14.5-nm-thick and 2-mu m-wide gold strip at 1.55 mu m. With a single-mode fiber, the lowest coupling loss of similar to 0.4 dB/facet is achieved with a 14.5-nm-thick and 5-mu m-wide gold strip at 1.55 mu m. The lowest insertion losses are obtained 8-9 dB with 1.5 cm-long gold strips of a limited thickness and width at both the wavelengths. We demonstrate a 10 Gbps optical signal transmission via the LRSPP waveguide with a 14 nm-thick, 2.5 mu m-wide, and 4 cm-long gold strip. These LRSPP waveguides have potential applications for optical interconnects and communications. (C) 2007 Elsevier B.V. All rights reserved.