Longwave plasmonics on doped silicon and silicides

The realization of plasmo-electronic integrated circuits in a silicon chip will be enabled by two new plasmonic materials that are proposed and modeled in this article. The first is ion-implanted Si (n-type or p-type) at the surface of an intrinsic Si chip. The second is a thin-layer silicide such as Pd2Si, NiSi, PtSi2 WSi2 or CoSi2 formed at the Si chip surface. For doping concentrations of 1020 cm(-3) and 1021 cm(-3), our dispersion calculations show that bound surface plasmon polaritons will propagate with low loss on stripe-shaped plasmonic waveguides over the 10 to 55 mu m and 2.8 to 15 mu m wavelength ranges, respectively. For Pd2Si/Si plasmonic waveguides, the wavelength range of 0.5 to 7.5 mu m is useful and here the propagation lengths are 1 to 2300 mu m. For both doped and silicided guides, the SPP mode field extends much more into the air above the stripe than it does into the conductive stripe material. (C) 2008 Optical Society of America.