In this letter, we demonstrate the possibility of an effective nano-scale FabryPerot interferometer in a sub-wavelength plasmonic waveguide in the form of a triangular groove on a metal surface, guiding channel plasmon-polaritons (CPPs). The resonant cavity is formed by two semitransparent metal membranes (mirrors) placed into the groove. Effective filtering effect of the cavity is demonstrated...

In this Letter, we explore transmission properties of a single subwavelength slit flanked by a finite array of grooves made on a thick metallic film. We identify three main mechanisms that can enhance optical transmission: groove cavity mode excitation (controlled by the depth of the grooves), in-phase groove reemission (controlled by the period of the groove array), and slit waveguide mode (co...

Trapping broadband electromagnetic radiation over a subwavelength grating, provides new opportunities for hyperspectral light-matter interaction on a nanometer scale. Previous efforts have shown rainbow-trapping is possible on functionally graded structures. Here, we propose groove width as a new gradient parameter for designing rainbow-trapping gratings and define the range of its validity. We...

A new type of hybrid ring coupler (or rat-race coupler) the gap-waveguide ring hybrid has been developed in this work. The advantages of the new gap-waveguide ring hybrid are low manufacturing cost since the good electrical contact between metal plates is not required, and lower transmission loss compared to microstrip line since there is no dielectric material needed. Therefore, the gap-wavegu...

In this paper, effects of the structural parameters on the optical characteristics of an add-drop filter, consisting of two straight waveguides and a micro-ring resonator (MRR), have been investigated. In this research, effects of MRR radius, the width of MRR and waveguide and the gap between MRR and waveguide, on free spectral range (FSR) and coupling coefficient have been studied. It is found...

In this paper, scattering and coupling problems of the directional coupler for the dielectric rectangular waveguides are analyzed by the mode-matching method in the sense of least squares for the fundamental mode incidence. This directional coupler is composed of three parallel dielectric rectangular waveguides cores which are placed at equal space in the dielectric medium. Namely, respective c...

A hybrid optical waveguide having a 90° sharp bend structure, composed of a dielectric straight waveguide, tapered dielectric strip waveguide, and microscale metal gap waveguide, is experimentally demonstrated in an attempt to improve the efficiency of light coupling between dielectric and plasmonic waveguides. Due to both the efficient structure of the taper and metal gap, the calculated coupl...

Method: At first, two optimized fineness levels were attained for both cement substituting materials used in this study (GGW as glass fine ˂ 38μm (GF), glass superfine ˂ 25μm (GSF) and EAFS as slag fine ˂ 75μm (SF), slag superfine ˂ 32μm (SSF)). In addition to control mortar (CM), four types of binary mortar mixtures were cast by substituting cement 5-20% with GGW (GF and GSF) and 10-30% with E...