Geometric optics method for surface plasmon integrated circuits

A fully-analytic expression is derived for the phase of reflection of surface plasmons at a semi-infinite boundary. We apply this phase of reflection result in the geometric optics method to calculate the properties of surface plasmon stripe waveguides. Comprehensive vectorial numerical computations are compared with the analytic method to show that it is accurate. The loss of the surface plasmon stripe waveguide is calculated using the geometric optics approach, which is also found to be in close agreement with numerical computations. The geometric optics approach may be used to obtain accurate results for other surface plasmon structures, such as microdisk or ring resonators, with greater efficiency and physical intuition than numerical computation.