Subwavelength confinement in an integrated metal slot waveguide on silicon

We demonstrate propagation losses of less than 0.8 dB/mu m in a metal slot waveguide on silicon with a predicted confinement substantially below the optical wavelength (similar to 1.55 mu m). We also show compact and efficient coupling of the high-confinement metal slot waveguide with a standard silicon dielectric waveguide with a coupling efficiency of approximately 2.5 dB per facet. (c) 2006 Optical Society of America.