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Leaky surface waves are found to exist at an interface between isotropic material with negative permittivity and uniaxially anisotropic material. Analytical solution is derived for such waves and confirmed by the finite-element eigenmode analysis.

We report our finding that nanoacoustic pulses can efficiently modulate the coupling between surface plasmons and the cavity mode in nanogratings, with promise to control surface plasmon polaritons with high temporal and spatial accuracies.

A high-order accurate pseudospectral frequency-domain (PSFD) method is used to analyze light scattering by plasmonic cylinders. Field coupling and enhancement within the gap of close spaced cylinders are examined.

The high-accuracy multidomain pseudospectral frequency-domain (PSFD) method is formulated to simulate the interaction of light and plasmonic structures. The excited electric field on a sinusoidal metallic surface by a transverse-electric optical wave is particularly studied.

We demonstrate the magnificent flexibility of the terahertz air-core pipe waveguides. By measuring waveguide attenuation spectra, we found that the pipe waveguides can be easily butt coupled with high coupling efficiency and low bending loss.

Investigating with pseudo-spectral time-domain method, we show that resonant scattering characteristics of Ag nanoparticle arrays are attributed to near-field surface magnetic field, instead of enhanced electric field induced by plasmonic coupling.

A finite-difference frequency-domain (FDFD) method based full-vectorial eigenmode solver is developed for analyzing anisotropic optical waveguides with arbitrary permittivity tensor. Guided modes on liquid-crystal-filled optical waveguides with different liquid-crystal molecular orientations are solved and discussed.

It is shown that suitable choice of the reflection-coefficient value of uniaxial perfectly matched layers is essental for achieving high-accuaracy analysis of leaky waveguide modes using the full-vectorial multidomain pseudospectral mode solver.

Light scattering from hexagonal-lattice silver-nanorod arrays embedded in nano-gap substrates are simulated using a high-accuracy 3D pseudospectral time-domain numerical scheme. A more realistic Drude-Lorentz material model is numerically implemented to facilitate efficient computation.

A full-vectorial finite element method based eigenvalue algorithm is developed for the band structure analysis of two-dimensional photonic crystals with arbitrary three-dimensional anisotropy under the out-of-plane wave propagation. The band edge diagram is then constructed.

The finite-difference frequency-domain method is adopted for analysis of air-core THz waveguides formed by Teflon rods. The guiding mechanism is found to be based on ARROW model and well confined guided THz-field can be obtained.

A finite-element method based eigenvalue algorithm is developed to investigate the intrinsic effect of anisotropy on the construction of complete band structures for two-dimensional non-diagonal anisotropic photonic crystals. Analysis for the triangular lattice is demonstrated.

The finite-difference frequency-domain method is formulated for calculating band structures of 2-D photonic crystals involving anisotropic materials. The director of the liquid crystal is allowed to rotate in the plane of the unit cell.

A novel method using imaginary-axis beam propagation for solving the eigenvalue problem of photonic crystals is developed. The methodology is demonstrated by collaborating with a high-order numerical scheme on the calculation of band diagrams.

The perfectly matched layers are incorporated into the full-vectorial multidomain pseudospectral waveguide mode solver for accurately determining the complex effective indices of leaky optical waveguides. Holey fibers are analyzed and compared with other methods.

A new full-vectorial multidomain pseudospectral mode solver based on pseudospectral methods for optical waveguides with arbitrary step-index profile is presented. The formulations are applied to optical fibers and rib waveguides and remarkable accuracy is demonstrated.

Eigenvalue equations for solving full-vector modes of optical waveguides are formulated using Yee-mesh-based finite difference algorithms. The effect of dielectric interface treatment on numerical accuracy is examined. Truncated-see paper for full abstract.

Fiber-optic couplers are the key components in many sensor and communication applications, including wavelength multiplexing and polarization beam splitting. Due to the deviation of the coupler geometry from circular symmetry, the difference in the coupling characteristics between x and y polarization states is usually called the form birefringence. Zheng [1] used the finite-element method to analyze the influence of the coupler’s degree of fusion on the form birefringence. His results showed that weakly fused couplers are non-birefringent, or isotropic (i.e., the coupling coefficients Cϰ=Cy) when the degree of fusion is 1.8 and 2.0 under the assumption that the normalized frequency V = ∞. However, for couplers with longer elongation the V-value in the waist region would not be large.

The fused tapered biconical optical fiber coupler has become the key type of fiber couplers [1]. Such coupler can be designed for wavelength-multiplexing and polarization beam splitting. Fig. 1 gives a sketch of the fused section of the coupler. In the neck region of the tapered coupler the light is guided by the boundary between the (reduced) fiber cladding and the external medium which is air unless some other potting material is employed. In this paper we describe a computer model which we have established for simulating the performance of the fused couplers based on rigorous analysis of the corresponding composite waveguide mode problems. The model can treat couplers with different cross sections resulting from different fusing conditions, for example, weakly-fused coupler composed of touching circular waveguides and strongly-fused coupler with dumbbell-shaped cross section. Recently, Okamoto [2] has used the effective-index method and the step approximation to analyze the mode coupling in the fused coupler and performed a detailed theoretical investigation of light coupling phenomena in wavelength-flattened couplers. The two-dimensional coupler structure was converted into an equivalent one-dimensional slab problem in the effective- index method. In our model the two-dimensional composite waveguide problem is solved in a full-wave vectorial manner and the polarization effect is fully taken into consideration. We shall show that the full-wave simulation results are significantly different from those based on the approximate analysis.