Backside Nanoslot Excited Sub-Wavelength Grating-Coupled Cu-Strip Plasmonic Waveguides

The backside nanoslot excited sub-wavelength grating-coupled Cu-strip silica-based plasmonic waveguides were developed using the finite difference time domain (FDTD) simulation method. The performance of the designed waveguides was simulated, and the effects of copper film thickness on plasmonic wave propagation were analyzed for relatively low propagation loss design. The designed waveguides could achieve unidirectional guiding of the excited surface plasmon polaritons (SPPs) with sub-wavelength lateral confinement and acceptable propagation length at microscale, and the recommended design for the sub-wavelength grating-coupled Cu-strip SPP waveguide was given, with the potential applications for the fiber-optic devices or elements. ASTAR (Agency for Sci., Tech. and Research, S’pore)