Surface-enhanced Raman scattering using gold nanoring substrates is studied. The measured enhancement factors of arrays of single nanorings and nanoring dimers are compared with that of an array of nanodisk dimers. The measured average enhancement factor for the single nanorings is 4.2 x 10(6). The experimental enhancement factors are compared with the electromagnetic enhancement factors predic...

Introduction: Many study shown the effectiveness dose enhancement with gold nanoparticles (GNPs), especially with low-energy x-rays. Recently, proton beam radiation therapy (PBRT) has attention as a treatment for tumors. The advantage in PBRT, which releases high dose at the controllable Bragg peak position that localized for Au target and the released dose increased in depth....

In this paper, a channel drop ring resonator filter based on two dimensional photonic crystal is proposed which is suitable for all optical communication systems. The multilayer of silicon rods in the center of resonant ring enables one to adjust resonant wavelength of the ring and enhance power coupling efficiency between ring and waveguide. Refractive index and radius of multilayer rods insid...

The present study investigated comparatively the impact of two types of input enhancement (i.e. textual vs. compound enhancement) on developing grammar ability in Iranian EFL setting. Sixty-five female secondary high school students were selected as a homogenous sample out of about a 100-member population based on Nelson language proficiency test. Then, their grammar ability was measured based ...

In this paper, contrast enhancement of dark image using Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) coefficients is proposed. Then the contrast enhancement is obtained by applying Dynamic Stochastic Resonance (DSR).The goal of dark image enhancement is to clearly visualize the features of the image. Two different coefficients DCTand DWT are used for implementing contras...

Absorption cross section of carbon soot clusters inside water microdroplets is calculated. Fractal geometry of carbon inclusions is considered with the fractal dimension D in the interval 1 ≤ D ≤ 3, which includes the trivial geometry (D = 3) as a limiting case. It is found that the absorption cross section of a soot cluster inside a water droplet is increased, compared to that in vacuum, by th...

We describe a resonator-based optical gyroscope whose sensitivity for measuring absolute rotation is enhanced via use of the anomalous dispersion characteristic of superluminal light propagation. The enhancement is given by the inverse of the group index, saturating to a bound determined by the group velocity dispersion. We also show how the offsetting effect of the concomitant broadening of th...

Highly organized supercrystals of Au nanorods with plasmonic antennae enhancement of electrical field have made possible fast direct detection of prions in complex biological media such as serum and blood. The nearly perfect three-dimensional organization of nanorods render these systems excellent surface enhanced Raman scattering spectroscopy substrates with uniform electric field enhancement,...

We report a five-fold overall enhancement of upconversion emission in NaYF(4) : Yb/Er nanocrystals when coupled with gold island films. Spectroscopic studies show that the enhancement factors are highly dependent on the exact spectral positions and excitation power density, with a largest enhancement factor of more than 12 observed at selected spectral positions, which may be attributed to diff...