A metallic coupler is proposed to interface a silicon on insulator (SOI) waveguide with a narrow hybrid Plasmonic waveguide (200× 200 nm). The device operation is investigated and optimized to attain the best tradeoff between the mode confinement and the propagation loss. Calculations reveal that a high confinement and low loss of the energy is achieved from a silicon slab waveguide into the dielectric slot of area 200×200 nm2 and a coupling efficiency of 70% (0.8 dB) at the 1.55 mm telecommunication wavelength can be achieved.

We study the supercontinuum generation in a nonlinear silica single layer Plasmonic waveguide. A major part of spectral broadening is related to soliton dynamics when an ultra-short pulse is launched in waveguide with anomalous GVD. Production of supercontinuum with 10th, 15th and 30th, orders bright solitons by considering all the nonlinear effects and dispersions i. e., inter-pulse Raman scattering, self-steepening, self-phase modulation, cross phase modulation, which indicates the existence of a supercontinuum propagation about 20 times broadening than initial width of input spectrum. Also, we consider the absorption effect of Plasmonic waveguide by calculating propagation length from propagation constant. The propagation length of Plasmonic is compared with the waveguide length and nonlinear length. At wavelength 1. 22μ m, the propagation length is obtained in the order of waveguide length which means one can consider the effect of absorption cannot alter the results. The nonlinear Plasmonic waveguides are suitable for integrated photonics because of subwavelength confinement of Plasmonic waveguides.

In this paper, the structure of a Plasmonic waveguide nanofilter based on monolayer MoS2 ring resonator is proposed and investigated. The structure performance is for a part of terahertz frequencies. Due to the low absorption and reflection of monolayer MoS2, considerable wave transmission and as a result, transparency, is provided. Filtering response caused by the proposed waveguide filter is resulted by the resonator which makes possible the coupling of the input and output nanoribbon waveguides. The structure operation has been simulated using the numerical method of finite difference time domain. The values of coupling efficiency, bandwidth at half of maximum, and quality factor, in operating wavelength of 1255 μm are respectively 0.78, 162 μm, and 7.7. The operating wavelength complies with the second resonance mode of the resonator. Also, the sensitivity of various structural indices in respect to manufacturing telorance is investigated. The proposed structure can have exnetsive application as a transparent electrode in photonic integrated circuits.

In this paper, the performance of a temperature sensor based on Plasmonic structure including a slot waveguide coupled with a stub resonator has been investigated. The results have been attained based on the dependency of dispersion equation, and so, the resonance frequency of the stub, to electric permittivity of the constructing material of the structure, InSb, which is also dependent to the ambient temperature. The design of the structure has been carried out for frequencies in terahertz spectra. The simulation results confirm an approximate linear relation between the resonance frequencies and ambient temperature, between 260-350 Kelvin. Also, a criterion has been assigned for evaluation the sensitivity and the performance temperature span of the proposed sensor. The calculated sensitivity is about 1×10-10 Kelvin per Hertz in the mentioned temperature interval. The sensor measurement resolution depends on the frequency resolution of the detection system. This simple sensor can be utilized in various chemical and bio systems.

In this paper, a high-performance graphene dielectric Plasmonic waveguide in the far infrared spectrum is proposed, which is one of the components of integrated photonic and optoelectronic circuits with various applications, including communications, military, medical, etc. The proposed waveguide geometric structure is composed of a rectangular cube layer with a semi-cylindrical ridge underneath (with a high refractive index material), rectangular cube substrate with a semi-cylindrical depression (with a low refractive index material), a sheet of graphene and the substrate of material with low refractive index, that the layers and sublayers are stacked on top of each other, respectively. Here, the surface plasmon polaritons (SPPs) modes are stimulated at the interface of graphene and dielectric. The propagation properties of SPPs modes have been investigated using the finite element method (FEM). The simulation results show that via modifying the geometrical parameters of the structure and tuning the chemical potential of the proposed graphene waveguide, a small normalized mode area ~〖10〗^(-4) and the propagation length ~〖10〗^3 μm are achieved. Therefore, it is recommended that the proposed waveguide can be used as a component of photonic devices due to relatively long propagation length and the strong confinement of light.

In this paper the transmittance of metal-insulator-metal (MIM) waveguides containing semi-circular ring shaped and rectangular ring shaped grooves are investigated theoretically in the 500 nm to 1700 nm wavelength range. By varying groove parameters their effects on the transmittance of the MIM waveguides are investigated. The results show that the transmittance spectra of the waveguides have maximum and minimum points, and by using appropriate parameters for the grooves it is possible to make the transmittance maximum or minimum at a required frequency. Therefore by using the ring shaped grooves in the MIM waveguides a frequency splitter is designed. The results show that the efficiency of an MIM waveguide containing the ring shaped groove for filtering a required frequency is higher than the efficiency of an MIM waveguide containing tooth shaped groove.

A graphene-based-hybrid Plasmonic waveguide (GHPW) with a unique geometric structure is designed for surface plasmon polariton guidance and modulation at the frequency area of 10 to 30 THz. The GHPW consists of a graphene layer in the middle, a high-density polyethylene (HDPE) gating layer, two interior dielectric delimiter layers, and two exteriors semi-cylinder Germanium substrates symmetrically embedded on both edges of the graphene. Because of the matchless semi-cylinder structure design, the electromagnetic wave interaction with graphene ultimate subwavelength SPPs strong confinement with long propagation length. Small normalized mode area of ~10-4 and long propagation length of 10.67-28.92 μm at Fermi energy of 1.0 eV is attained for SPPs modes propagation of the GHPW in the frequency bound of 10-30 THz and semi-cylinder radius R > 450 nm, respectively. By controlling the graphene Fermi energy, it is found that the structure has a modulation depth higher than 20 % for the frequency band of 10-30 THz and arrives at the peak of approximately 100 % at a frequency greater than 28.75 THz. To benefit from the great broadband MIR propagation and modulation efficiency, the GHPW may promise different MIR waveguides, modulators, photonic, and optoelectronic devices.

Plasmons in graphene have unusual properties and offer promising prospects for Plasmonic applications covering a wide frequency range from terahertz to the visible spectrum, and many studies have been conducted on plasmon modes in graphene. In this research, a symmetric graphene Plasmonic waveguide has been proposed to improve the waveguide performance in the mid-infrared range, and the Plasmonic properties of graphene have been investigated by the finite element method and using COMSOL software. The structure of this waveguide is in the form of two elliptical nano-cylinders coated with graphene, which are placed symmetrically on each side of a thin sheet of Al2O3. The results obtained from the simulation show that by changing the geometric parameters of the proposed structure and changing the type of materials, the propagation length of the modes is more than 8 micrometers, and the normalized mode area is obtained in the order of 10-6. For this reason, the proposed waveguide has promising applications in photonic integrated circuit components and other nanoscale devices.

In this study, waveguide properties of graphene nanoribbon on hBN and a substrate were investigated. Precisely, the Plasmonic mode properties including the real part of refractive index, the propagation length, figure-of-merit (FoM) on frequency, the Fermi energy of graphene, and the substrate in the mid-IR spectrum range were inspected. The simulated results show that graphene waveguide is intensively sensitive to the frequency, Fermi energy and structural geometry in the mid-IR range. Also, the propagation length for a Fermi energy of 0. 3 (0. 9) eV in the frequency range of 1375 cm-1 to 1600 cm-1 reaches from 0. 1 (0. 4) to 0. 38 (4. 15) µ m, where it shows a 3-(10)-fold enhancement.

Abstract Plasmons in nanometer structures are caused by the interaction between electromagnetic waves and electrons on the metal surface. In this article, a comprehensive and detailed investigation of the effect of effective parameters on the performance of structured MIM waveguides (metal-insulator-metal) has been carried out. These structures are widely used in sensor applications based on refractive index changes or filters. This paper examines the impacts of altering factors like waveguide size, metal type, and insulation while also proposing novel structures with circular and square resonators,Then we simulated the structure of the MIM waveguide connected to the cavity of the T-shaped resonator for different values for the length L of the cavity, It is possible that this issue has a good use in filters and systems with high bandwidth to separate channels  . Also,the properties of surface plasmon polaritons emission were investigated in the case where a resonator is vertically connected to it. The transmission diagram had compared to the MIM waveguide without resonator.