We have theoretically investigated twin-core all-solid photonic bandgap fibers (PBGFs) for evanescent wave sensing of refractive index within one single microfluidic analyte channel centered between the two cores. The sensor can achieve ultrahigh sensitivity by detecting the change in transmission. We find novel features in the sensing characteristics: the sensitivity is higher at the short wav...

This article presents a high gain patch antenna with negative refractive index (NRI) superstrate for the application of Radio frequency energy harvesting system. Triangular split ring resonators (TSRR)-strip line are used as a NRI superstrate to enhance the gain of the patch antenna. It is demonstrated that the proposed triangular split ring resonator (TSRR) structure metamaterial yields negati...

We report the experimental demonstration of a broadband negative refractive index obtained in a labyrinthine acoustic metamaterial structure. Two different approaches were employed to prove the metamaterial negative index nature: one-dimensional extractions of effective parameters from reflection and transmission measurements and two-dimensional prism-based measurements that convincingly show t...

Laser diffraction is one of the most widely used methods for particle size analysis of micron and submicron size powders and dispersions. It is quick and easy and provides very consistent, repeatable information. Since these instruments use scattered light intensity to determine particle size, knowledge of the optical properties, specifically the complex refractive index of the material being a...

A new integrated optical sensor chip is proposed, based on a modified distributedfeedback (DFB) semiconductor laser. The semiconductor layers of different refractive indices that comprise a laser form the basis of a waveguide sensor, where changes in the refractive index of material at the surface are sensed via changes in the evanescent field of the lasing mode. In DFB lasers, laser oscillatio...

a negative index of refraction over a band of microwave frequencies1. This demonstration of a previously unexploited electromagnetic (EM) property proved the importance of engineered materials and has resulted in an extraordinary amount of continued development by scientists working in optics, electromagnetism, physics, engineering, and materials science. Experimental results revealing new phen...

Ultrasonic computed tomography (UCT) is one of the methods capable of tissue characterization. It is expected to provide not only a quantitative image but also diagnostic information. As in X-ray CT, UCT requires a projection data to reconstruct a cross-sectional image. In UCT such projection data are derived from the received broadband ultrasonic signal. In this paper, two methods for deriving...