Split-ring resonators (SRRs) have been the subject of investigation as plasmonic sensors that operate by sensing plasmon resonance shift δλ when exposed to a medium with refractive index change δn. However, conventional planar SRRs their fields spread into substrates, reducing accessible volume and its performance. Such limitation can be eradicated vertical in which localized SRR gaps are lifted off from substrate, allowing for greatly enhanced sensitivity. Here, we demonstrate highest...

It is desirable to extend the surface-enhanced Raman scattering (SERS) from conventionally used visible range into infrared region, because fluorescence background lower in long-wavelength regime. To do this, it important have a SERS substrate suitable for operation. In this work, we report near operation based on substrates employing star-shaped gold/silver nanoparticles and hyperbolic metamaterial (HMM) structure. We first fabricate which are separated silver film by thin dielectric layer....

In this paper, a periodic metallic–dielectric nanorod array which consists of Si nanorods coated with 30 nm Ag thin film set in hexagonal configuration is fabricated and characterized. The fabrication procedure performed by using nanosphere lithography reactive ion etching, followed thin-film deposition. mechanism the surface gap plasmon modes supported structure numerically demonstrated three-dimensional finite element method. measured simulated absorptance spectra are observed to have same...

We numerically and theoretically investigate a highly sensitive tunable plasmonic refractive index sensor that is composed of metal-insulator-metal waveguide with side-coupled nanoring, containing silver nanorods using the finite element method. Results reveal presence in nanoring has significant impact on sensitivity tunability performance. It gives flexible way to tune system response proposed structure. Our designed 2080 nm/RIU (RIU unit) along figure merit quality factor 29.92 29.67,...

Herein, we design a high sensitivity with multi-mode plasmonic sensor based on the square ring-shaped resonators containing silver nanorods together metal-insulator-metal bus waveguide. The finite element method can analyze structure's transmittance properties and electromagnetic field distributions in detail. Results show that coupling effect between waveguide side-coupled resonator enhance by generating gap plasmon resonance among nanorods, increasing cavity mode resonator. suggested...

An ultra-high plasmonic refractive index sensing structure composed of a metal-insulator-metal (MIM) waveguide coupled to T-shape cavity and several metal nanorod defects is proposed investigated by using finite element method. The designed MIM can constitute resonance zone the effectively trap light in cavity. results reveal that both size wider rectangular length narrower are primary factors increasing sensitivity performance. achieve as high 8280 nm/RIU (RIU denotes unit), which highest...

A plasmonic metal-insulator-metal waveguide filter consisting of one rectangular cavity and three silver baffles is numerically investigated using the finite element method theoretically described by resonance mode theory. The proposed structure shows a simple shape with small number structural parameters that can function as sensor property, high sensitivity figure merit, wide bandgap. Simulation results demonstrate could significantly affect condition remarkably enhance performance...

Plasmonic effect using a cross-hair can convey strongly localized surface plasmon modes among the separated composite nanostructures. Compared to its counterpart without cross-hair, this characteristic has remarkable merit of enhancing absorptance at resonance and make structure carry out dual-band plasmonic perfect absorber (PPA). In paper, we propose design novel PPA with gathering four metal-shell nanorods operating visible near-infrared regions. Two peaks 1050 nm 750 maximal 99.59%...

In this study, locally grown bamboo ( Gigantochloa spp.) was used as feedstock for pyrolysis production of biochar under various temperatures (400–800°C). The resultant biochars were tested their performance in adsorptive removal the methylene blue (MB) dye. scope adsorption experiment includes effects adsorbent dosage, solution pH, initial adsorbate concentration, and contact time. data confirmed that temperature has a significant effect on performance, whereas pyrolysed at 500°C (BC500)...

This work proposed a multiple mode Fano resonance-based refractive index sensor with high sensitivity that is rarely investigated structure. The designed device consists of metal–insulator–metal (MIM) waveguide two rectangular stubs side-coupled an elliptical resonator embedded air path in the and several metal defects set bus waveguide. We systematically studied three types structures employing finite element method. Results show surface plasmon mode’s splitting affected by geometry sensor....

Amorphous thin films of Ge(2)Sb(2)Te(5), sputter-deposited on a ZnS-SiO(2) dielectric layer, are investigated for the purpose understanding structural phase-transitions that occur under influence tightly-focused laser beams. Selective chemical etching recorded marks in conjunction with optical, atomic force, and electron microscopy as well local diffraction analysis used to discern complex features created broad range powers pulse durations. Clarifying nature phase transitions associated...

We propose a plasmonic perfect absorber (PPA) based on metal nanorod arrays with the connected veins for ultra-sensitive refractive index (RI) sensing applications in near-infrared region. The physical origin is explained through absorptance/reflectance spectra, distribution of electric/magnetic field intensity, surface charge density, height and gap distance. designed PPA can constitute cavity resonance center serve as sensor. There huge difference absorptance reflectance between case...

A highly sensitive metal-insulator-metal plasmonic filter with a centrally coupled ring resonator containing silver nanorod defects is numerically investigated by using the finite element method and theoretically characterized temporal coupled-mode theory. The proposed structure can function as refractive index sensor compact in design higher sensitivity figure of merit (FOM). Simulation results reveal that presence will significantly affect performance, which provides tunable way to enhance...

Abstract A plasmonic nanostructure (PNS) which integrates metallic and dielectric media within a single structure has been shown to exhibit specific properties are considered useful in refractive index (RI) sensor applications. In this paper, the simultaneous realization of sensitivity tunability optical PNSs consisting alternative Ag nanosphere/nanorod array have proposed compared by using three-dimensional finite element method. The system can support hybrid modes localized surface...

In this paper, the coupled Ag-shell/dielectric-core nanorod for sensor application is investigated and different dielectric core plasmonic metamaterial adopted in our design. The operational principle based on concept of combining lattice resonance, localized surface plasmon resonance (SPR), cavity modes within nanostructure. underlying mechanisms are numerically by using three-dimensional finite element method numerical results solid Ag nanorods included comparison. characteristic...

Numerical investigation of resonant peak by modifying the number protruded metal nanorods (MNRDs) and core material in nanoshells for near field intensity are explored means finite element method. The surface plasmon effect arising from cases with/without MNRDs was compared along with that arose their solid counterparts. A strong tunable coupling enhancement effects corresponding to transverse resonance (SPR) cavity (CPR) modes observed. It is found spectra obtained silver silver-shell...

An ultra-broad bandgap plasmonic based filter that consists of a metal-insulator-metal waveguide with symmetrical stubs and defects is designed investigated for the first time. A tunable wide can be achieved by introducing into larger width about 1.35 times compared to its counterpart without acquired. It found both number periods play crucial roles affect performance, which attributed change effective refractive index plasmon resonance modes in proposed structure. The has potential...

We propose an ultra-compact plasmonic nanostructure to realize multiple Fano resonance (FR) modes, comprising two separated metal–insulator-metal (MIM) bus waveguides side-coupled with a circular ring, including air path, and this design is less considered before in the MIM-cavity system. The sensing performance can significantly improve by introducing path induce new coupled structure, generating FR modes unique optical properties. Using finite element method, we numerically simulate...

The possibility of constructing an optical sensor for temperature monitoring based on the Goos-Hänchen (GH) effect is explored using a theoretical model. This model considers lateral shift incident beam upon reflection from metal-dielectric interface, with becoming function due mainly to dependence properties metal. It found that such can be most effective by long wavelength p-polarized light at almost grazing incidence onto metal, where significant variation negative GH shifts observed as...

Using a femtosecond laser, we have transformed the laser-direct-writing technique into highly efficient method that can process AgO(x) thin films Ag nanostructures at fast scanning rate of 2000 μm(2)/min. The processed exhibit broad-band enhancement optical absorption and effectively function as active SERS substrates. Probing plasmonic hotspots with dyed polymer beads indicates these are uniformly distributed over treated area.