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Recent advances in nano-optics elicit a growing need for more efficient numerical treatments of light-matter interaction in stratified backgrounds. While being known for its many favorable properties, usage of the surface integral approach is hindered by numerical difficulties associated with layered-medium Green's functions. We present an efficient and robust implementation of this approach, addressing the limiting issues. The singularity extraction method is generalized to account for the occurring secondary-term singularities. The resulting scheme thus allows for arbitrary positioning of the scatterers. Further, the laborious matrix-filling process is dramatically accelerated through a simple and robustly-devised, spatial interpolation scheme, completely devoid of integral evaluations. The accuracy and versatility of the method are demonstrated by treating several representative plasmonic problems.

Large area photonic crystal cavities are devices of interest for photovoltaics, optoelectronics, and solid-state lighting. However, depending on their dimensions they pose a large computational challenge. Here, we use a local density approach to avoid direct simulation of the device. We capture the effect of both ideal and distorted photonic crystals in an effective mass and an effective potential. We use these to map the problem of calculating the electromagnetic field modes to solving a simple time-independent Schrödinger equation. We show that, in the case that the hole radius varies quadratically as a function of position, the eigenmodes of the photonic crystals can be described by the corresponding eigenmodes of the quantum harmonic oscillator with typical agreements well above 90%.

We characterize bending losses of curved plasmonic nanowire waveguides for radii of curvature ranging from 1 to 12 microm and widths down to 40 nm. We use near-field measurements to separate bending losses from propagation losses. The attenuation due to bending loss is found to be as low as 0.1 microm(-1) for a curved waveguide with a width of 70 nm and a radius of curvature of 2 microm. Experimental results are supported by Finite Difference Time Domain simulations. An analytical model developed for dielectric waveguides is used to predict the trend of rising bending losses with decreasing radius of curvature in plasmonic nanowires.