Asymmetric resonances and field enhancement of hybrid plasmon-waveguide modes

Abstract

The planar metal/dielectric structures based on a CdTe waveguide separated from a metal layer by a layer of silicon dioxide support excitation of propagating hybrid plasmon-waveguide modes. The intercoupling of plasmon and waveguide modes results in the appearance of asymmetric resonance line shapes in spectra. The field enhancement of the hybrid modes is characterized by the Fano and plasmon-induced transparency-like line shapes in the attenuated total reflection spectra. The rigorous electromagnetic theory is used to analyze the field distribution in resonance regions. In this paper, redistribution of the electromagnetic field between the coupled modes is demonstrated. We demonstrate the appearance of hybrid symmetric and antisymmetric plasmon-waveguide modes in the structure. Obtained results can lead to development of applications in sensing and enhanced spectroscopies.