Hybrid representations of asymmetrically excited surface plasmon self-interference at a planar dielectric/metal interface.

We introduce a hybrid representation to describe asymmetrically excited surface plasmon (SP) self-interference at a planar dielectric/metal interface. The hybrid representation combines a ray model, angular spectrum representation, near-field spatial frequency analysis, and parameter characterization to investigate the incidence coupling and spatial resolution degradation of the SP self-interference. We also propose SP numerical aperture for self-interference virtual probe imaging. We explain the shift in the main peak in asymmetrical excitation. Individual models are used to study the various characteristic features in detail, and physical insights are gained. We examine the consistency of the results obtained using the different models and demonstrate the effectiveness of the hybrid representation for describing the asymmetrically excited SP self-interference.