English

The Surface response around a sharply resonant surface polariton mode is simply a Lorentzian

Optics 2021-07-07 v3

Abstract

At the planar interface between a material and vacuum, the complex surface response S(omega)=[eps(omega) 1]/[eps(omega)+1], with eps(omega) the relative complex dielectric permittivity of the material, exhibit resonances, typical of the surface polariton modes, when eps(omega) ~ 1. We show that for a moderately sharp resonance, S(omega) is satisfactorily described with a mere (complex) Lorentzian, independently of the details affecting the various bulk resonances describing ) eps(omega). Remarkably, this implies a quantitative correlation between the resonant behaviors of Re[S(omega)] and Im[S(omega)], respectively associated to dispersive and dissipative effects in the surface near-field. We show that this "strong resonance" approximation easily applies, and discuss its limits, based upon published data for sapphire, CaF2 and BaF2. Extension to interfaces between two media or to a non planar interface is briefly considered.

Keywords

Cite

@article{arxiv.2102.06948,
  title  = {The Surface response around a sharply resonant surface polariton mode is simply a Lorentzian},
  author = {J. C. de Aquino Carvalho and D. Bloch},
  journal= {arXiv preprint arXiv:2102.06948},
  year   = {2021}
}

Comments

accepted for publication in Optics Letters