Propagation of TM surface modes in a taper slab waveguide with anisotropic metamaterials

The TM surface mode propagation properties in a taper slab waveguide with an anisotropic metamaterial core and common material claddings are investigated. Through Maxwell's equations, the dispersion, reflection coefficient, transmission coefficient and power loss were extracted for the TM surface modes. Then, some characteristic curves are plotted for different metal filling ratios or different frequencies. From these curves, it is found that: (1) as waveguide length L = 7.7 μm, the reflection coefficient is near 0.99; (2) the transmission coefficient |ct|2≤0.1ct2≤0.1 or even |ct|2≤0.05ct2≤0.05; (3) the power loss Δp/p ≥ 0.98 or even Δp/p ≥ 0.99, which means extra strong reflection or extra big energy loss can exist in the taper waveguide. These new properties for TM surface modes propagation will benefit us to design extra strong reflectors or novel absorbers in the future.