Abstract
To reveal origins of resonance characteristics of multilayer interference structures, we developed an ab initio spatial coupled-mode theory using the approximations of general electromagnetic theory of wave propagation in stratified media. In contrast to the conventional coupled-mode theory, the coefficients of developed coupled-mode models, which describe the Fano resonance behavior of interference field enhancement, are given by analytical functions of structural and optical parameters of the resonance systems. The results of analytical modeling of low- and high-loss resonator systems supporting waveguide, Fabry-Pérot, symmetric, and antisymmetric plasmonic normal modes agree very well with electromagnetic numerical simulations. We demonstrate also that the conventional spatial phenomenological coupled-mode theory is accurate only for low-loss structures.
2 More- Received 12 November 2021
- Revised 13 March 2022
- Accepted 13 July 2022
DOI:https://doi.org/10.1103/PhysRevA.106.023507
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