Nanoparticles of noble metals exhibit localized surface plasmons (LSPs) associated with the enhancement an electromagnetic field due to its localization in nanometric domains at nanoparticles. We demonstrate plasmonic photoelectric conversion from visible near-infrared wavelength without deteriorating by using electrodes which gold nanorods are elaborately arrayed on a TiO2 single crystal.

We report the stoichiometric evolution of oxygen via water oxidation by irradiating a plasmon-enhanced photocurrent generation system with near-infrared light (λ: 1000 nm), in which gold nanostructures were arrayed on surface TiO2 electrode. It is considered that multiple electron holes generated plasmon-induced charge excitation led to effective recovery after transfer from TiO2. The proposed containing nanostructured electrode may be promising artificial photosynthetic using light.

We analyze the localized surface plasmon resonance spectra of periodic square lattice arrays gold nano-disks, and we describe numerically experimentally effect disorder on width, spectrum, EM field enhancement in increasingly randomized patterns.The structure shows a narrower stronger extinction peak, conversely observe an increase up to (1 -2) × 10 2 times as is gradually introduced.This allows for simpler, lower resolution fabrication, cost-effective light harvesting solar cell sensing...

Abstract Over more than 40 years since its discovery, surface‐enhanced Raman scattering/spectroscopy (SERS) has attracted substantial attention as a tool for fundamental research in surface science and potential analytical sensing applications. This review aims to concisely summarize the essential principles of both physical chemical processes underlying signal enhancement, well elements broader field plasmonics that are most relevant SERS. In order make sense overwhelming variety SERS...

Light trapping photonic crystal (PhC) patterns on the surface of Si solar cells provides a novel opportunity to approach theoretical efficiency limit 32.3%, for light-to-electrical power conversion with single junction cell. This is beyond implied by Lambertian ray ~ 29%. The interference and slow light effects are harnessed collecting even at long wavelengths near band-gap. We compare two different methods patterning, that can be extended large area patterning: 1) laser direct write 2)...

There is a growing need for novel methods to modify the surfaces of wide range materials over large areas. Here, we demonstrate creation low-reflectance (R<2%) in near-to-mid infrared (IR) spectral window 2–20 μm by ablating W, Al, and Cu with high average intensity 20–120 TW/cm2, 200 fs laser pulses at 1030 nm wavelength. The chemical modifications ablation under ambient room conditions were analyzed using X-ray photoelectron spectroscopy (XPS). results show consistent decrease metallic...

Nanoparticles of noble metals exhibit localized surface plasmons (LSP) associated with enhancement the electromagnetic field due to its localization in nanometric domains at nanoparticles. Especially, nanogap metallic structures show strong position. This can be achieved up 105 times larger than incident light field. We have explored possibility use for nanogap-assisted plasmon nanolithography. For this purpose, monodisperse arrays consisting pairs rectangular gold nanoblocks separated by...

The creation of anti-reflective surfaces is reliant on the engineering surface textures and patterns to enable efficient trapping or transmission light. Here we demonstrate layers composed hierarchical nano/microscale features that are prepared Si using a combination wet dry etching processes, which both scalable affordable. performance structured was tested through optical measurements reflectance, transmittance, scattering spectra from visible mid-infrared wavelength regions, results were...

This work reports fabrication of inverse silica opal photonic crystal structures from direct polystyrene micro sphere opals using low-temperature sol-gel infiltration silica, and examines performance these crystals as environmental refractive index sensors. Sensitivity the spectral position optical attenuation stop gaps is found to allow detection changes by amount ~10(-3). The high value sensitivity, which comparable with those other sensing techniques, along simplicity setup required for...

Microphotonic sensors have been actively studied with increasing demands for label-free biosensing in medical diagnoses and life sciences. For high-throughput low-cost sensing, a high sensitivity is crucial eliminating the pre-concentration process, while simple setup of also desirable. This paper demonstrates super-sensitivity protein, which satisfies these requirements. The key device photonic crystal nanolaser, particular nanoslot. Even using setup, nanolaser achieves an extraordinary-low...

Optical properties of localized surface plasmon resonance (LSPR) in Au/Ag alloy were investigated experimentally and numerically. It was found that LSPR spectra nanostructures at near-infrared wavelengths changed drastically the 50% mole fraction. Both experimental results finite-difference time-domain simulations using obtained n, k values showed a similar tendency. At molar fraction, electromagnetic field enhancement reached almost same value as pure Au.

In this study, biodiesel effects on transient needle motion and near-exit flow characteristics of a single-orifice high-pressure diesel injector were investigated in terms needle-lift, speed, exit velocity structure under various injection pressures. Ultrafast x-ray phase-contrast imaging technique was employed study to analyze the characteristics. High-energy sub-nanosecond pulses have potential visualize inside nozzle dense supersonic which speed reaches over 600 m/s. Transient flows can...

Surface enhanced Raman scattering (SERS) was measured on periodic and randomly arranged patterns of Au nano-bricks (rectangular parallelepipeds).Resonant SERS conditions were investigated a near-IR dye deposited nanoparticles.Random mixtures with different aspect ratio R showed stronger enhancement as compared to constant (R varies from 1 4).SERS mapping revealed up ∼ 4 times signal increase at the hot-spots.Experimental observation is verified by numerical modeling qualitatively consistent...

Precious metal alloys enables new possibilities to tailor materials for specific optical functions. Here we present a systematic study of the effects nanoscale alloying on permittivity Au-Ag-Cu metals at 38 different atomic mixing ratios. The was measured and analyzed numerically by applying Drude model. X-ray diffraction (XRD) revealed face centered cubic lattice alloys. Both, spectra XRD results point towards an equivalent composition-dependent electron scattering behavior. Correlation...

Detailed spectral analysis of radiation absorption and scattering behaviors metasurfaces was carried out via finite-difference time-domain (FDTD) photonic simulations. It revealed that, for typical metal-insulator-metal (MIM) nanodisc metasurfaces, absorbance cross-sections exhibit a ratio σabs/σsca = 1 at the peak position. This relationship likewise found to limit attainable photo-thermal conversion efficiency in experimental application contexts. By increasing due optical materials, such...

We use a surface-enhanced infrared absorption (SEIRA) spectroscopy, useful sensing and surface analysis method complimentary to the Raman scattering for individual enhancement of specific molecular vibration bands fingerprinting vibrations.SEIRA spectroscopic measurement using metal hole array (MHA) is demonstrated with high spectral selectivity.The IR peaks are enhanced up 10 times at transmission peak MHA structure when electromagnetic field localized on walls inside holes.Experimental...

An intricate relationship is revealed between the intensity of surface‐enhanced Raman scattering (SERS) and optical extinction. The unusual trends SERS decrease while extinction increases observed in experiments fully explained for first time. well known to be strongly correlated with at excitation Stokes wavelengths, but dependence more involved than simple product two enhancements. radiative nonradiative losses, different affect Dye molecules are shown experimentally numerically experience...

Maximum absorption of light using plasmonic perfect absorbers (PPAs) is highly desired in the field energy harvesting, sensing, as well photothermal sources. We reveal how optical properties several popular metals (Au, Ag, Cu, Pd) and insulators (SiO2, Si, ZnO) affect performance PPAs at mid-infrared (IR) wavelengths. At this wavelength range radiation a system are also linked to its thermal conductivity; hence, work thinner insulator layers around 10 nm thickness given special focus....

Abstract Thermo-optical properties of the nanodisc and metal hole array plasmonic perfect absorber (PPA) metasurfaces were designed characterized at mid-infrared wavelengths. Both, radiation emitter detector systems operating in various spectral domains are highly sought after for a diverse range applications, one example being future sensor networks employed internet-of-things. Reciprocity absorbance emittance is shown experimentally, i.e., PPAs demonstrated to follow Kirchhoff’s law where...

A hydrogen sensor based on plasmonic metasurfaces is demonstrated to exhibit the industry-required 10 s reaction time and sensitivity. It consists of a layer either Y or WO3 sandwiched between top Pd nanodisk Au mirror at base. The phase change (Y, WO3) reacts with hydrogen, corresponding refractive index (permittivity) detected by spectral shift resonance dip in reflectance IR window. This direct readout permittivity due uptake fast facilitated radiation field enhancement extending into...

The emission intensity of a GaInAsP photonic crystal nanolaser is affected by the pH solution, in which immersed. This phenomenon can be explained change redox potential, modifies filling electrons at surface states semiconductor and hence nonradiative recombination. allows to simultaneously independently detect refractive index electric charges near on basis variation wavelength intensity, respectively. paper demonstrates this function through alternate deposition charged polyelectrolytes...

We demonstrate the use of plasmonic extraordinary transmission at IR wavelengths for surface-enhanced infrared absorption (SEIRA) spectroscopy in gas sensing.Gas detection was performed through nondispersive (NDIR) absorption.The sensitivity SF 6 is increased around ∼27 times with metal hole array (MHA) microstructures placed on cell mirrors, as compared non-structured mirrors; an change 2% per 100 ppm obtained a standard commercial pyroelectric detector.Down-sizing IR-sensors to sub-1 mm...