Slab Waveguide Sensor with Left-handed Material Core Layer for Detection an Adlayer Thickness and Index

A four-layer slab waveguide structure with a lossy left-handed material (LHM) core layer is investigated as a surface sensor for detection any change in an adlayer thickness and refractive index. The sensitivities of the effective refractive index to any change in the refractive index/thickness of the adlayer are derived and studied with the parameters of the LHM. It is found that a slight change in the real parts of the permittivity and permeability of the LHM can significantly improve the sensitivity of the proposed sensor

Dispersion properties of anisotropic-metamaterial slab waveguide structure

The dispersion properties of guided waves in an anisotropic film sandwiched between a left-handedmaterial (LHM) and a dielectric are investigated in this work. Detailed mathematical derivationof the dispersion relation is presented. Both the anisotropic guiding layer and the LHM are assumedto be dispersive. Many interesting features have been found. The dispersion properties exhibita slight dependence on the parameters of the anisotropic guiding layer whereas they showa significant change with any perturbation in some of the LHM layer parameters, especially forω>5.2GHz.The dispersion properties of guided waves in an anisotropic film sandwiched between a left-handedmaterial (LHM) and a dielectric are investigated in this work. Detailed mathematical derivationof the dispersion relation is presented. Both the anisotropic guiding layer and the LHM are assumedto be dispersive. Many interesting features have been found. The dispersion properties exhibita slight dependence on the parameters of the anisotropic guiding layer whereas they showa significant change with any perturbation in some of the LHM layer parameters, especially forω>5.2GHz

Dispersion properties of slab waveguides with double negative material guiding layer and nonlinear substrate

The dispersion properties of transverse electric nonlinear waves in a three-layer slab waveguide which consists of a double negative material (DNM) guiding layer sandwiched between an intensity-dependent refractive index substrate and semi-infinite linear dielectric cover are investigated. The dispersion properties for self-focusing and self-defocusing substrate nonlinearity are presented. The effects of the negative parameters of the DNM on the dispersion characteristics are investigated

Optimization of transverse electric peak-type metal-clad waveguide sensor using double-negative materials

In a very recent work, a transverse electric peak-type metal-clad waveguide optical sensor was proposed in which a double-negative material (DNM) was used as a guiding layer. The sensor was found to exhibit a considerable angular shift of the reflectance peak for small changes in the refractive index of the analyte, due to the DNM layer. In this work, the optimization of the structure parameters is investigated to find out the most appropriate metal and its optimal thickness. Moreover, the optimal DNM layer parameters corresponding to the highest sensitivity are explored. Our calculations reveal that metals with high absolute value of the real part of the permittivity correspond to sharper peaks. Moreover, as the absolute value of the real part of both ε and μ of the DNM increases, the reflectance peak becomes sharper and the dip following the peak becomes deeper

Transverse magnetic peak type metal-clad optical waveguide sensor

Transverse magnetic (TM) waves in a four-layer slab waveguide structure are studied for optical sensing applications. The structure consists of a semi-infinite substrate, a thin metal layer, a medium with negative permittivity and permeability as a guiding layer, and a semi-infinite layer as a cover. The proposed sensor is operated in reflection mode in which the angular position of the reflectance peak is used to detect small changes in the refractive index of the cover medium. The optimal structure parameters that correspond to the sharpest and highest peak are presented. The results reveal that for aluminum metal layer, a thickness of about 9 nm represents the optimum metal thickness. Moreover, the thickness, negative permittivity, and negative permeability of the guiding layer are found to have great impacts on the performance of the proposed optical waveguide sensor

Peak type metal-clad waveguide sensor using negative index materials

A four-layer metal-clad structure was considered as an optical sensor for refractometry applications. The structure had a negative index material (NIM) as a core layer. The structure parameters were chosen for so that the reflectance profile of the proposed structure shows a sharp peak, which is appropriate for sensing applications. The sensor was found to exhibit a considerable angular shift of the reflectance peak for small changes in the refractive index of the analyte, due to the NIM layer

Metal-clad waveguide sensor using a left-handed material as a core layer

A four-layer waveguide structure comprising a dielectric substrate, a metal layer, a left-handed material (LHM) as a guiding layer, and a cladding is investigated as a metal-clad waveguide sensor. Fresnel reflection coefficients are used to study the resonance dips at which the reflectance minimizes. Our calculations show that the proposed structure has a preference over the surface-plasmon resonance structure since it gives a much sharper reflectance dip and can achieve considerable sensitivity improvement. The effects of the LHM permittivity, permeability, and thickness on the reflectance curves is studied

Slab waveguide sensor utilizing left-handed material core and substrate layers

Propagation of transverse electric (TE) polarized light in two three-layer slab waveguide structures comprising left-handed materials (LHMs) is studied for sensing applications. The LHM layer occupies the core layer in the first structure and the substrate layer in the second structure. The sensitivity of the effective refractive index of the guided mode to any change in the index of an analyte medium located in the cladding region is derived and studied. The optimal structure parameters corresponding to the highest sensitivity are found. The results reveal that the sensitivity of the second structure with LHM substrate is much higher than that of the first with LHM core layer. The sensitivity can reach up to 70% for the LHM substrate structure for some waveguide configurations whereas it can reach up to 45.5% for the LHM core structure. The sensitivities of the two structures are found to be significantly high when compared