Wedged negative dielectric gap waveguide has been studied theoretically.
FDTD simulations show adiabatic wavenumber conversion in coupled mode of surface plasmon polariton along the wedged structure.
In addition, field enhancement has been observed at the output of the wedged structure even in large propagation loss of metals.
We propose wedged negative dielectric gap waveguide as an efficient nano-optical coupler between optical fibers to nano-optical circuits.
Propagation modes in metal gap waveguide formed on a prism have been studied experimentally by using attenuated total reflection method.
Coupled modes of surface plasmon polariton in two metal/dielectric interfaces are studied experimentally by using attenuated total reflection (ATR) method. Metal/dielectric interfaces are fabricated as metal gap waveguides on a high refractive index prism. ATR spectra are analyzed by mode analysis for the metal gap waveguide. A tapered metal gap waveguide is proposed as an effcient coupler from optical fibers to nano-optical circuits. FDTD simulations show adiabatic conversion of wavenumber of coupled surface plasmon polariton.