Topic
Step-index profile
About: Step-index profile is a research topic. Over the lifetime, 3104 publications have been published within this topic receiving 53199 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a rapid and accurate method for determining the Brewster angle by the Abeles condition is described, independent of index of refraction of the substrate and thickness of the film.
Abstract: A rapid and accurate method for determining the Brewster angle by the Abeles condition is described. The technique is independent of index of refraction of the substrate and thickness of the film. The indices of refraction can be measured to an accuracy range of about 0.0002 to 0.0006.
55 citations
TL;DR: In this paper, a two-dimensional nanoscale structure for sensing which consists of a metal-insulator-metal (MIM) waveguide with a defect, is designed and numerically simulated by using the finite element method (FEM).
55 citations
TL;DR: In this paper, a method for measuring the refractive index profile of optical glass fibres is described, which simply monitors the reflection of a focused laser beam from a polished fibre end face.
Abstract: A new method for measuring the refractive index profile of optical glass fibres is described. This simply monitors the reflection of a focused laser beam from a polished fibre end face. Detailed tests on the accuracy and resolution of the method are described and the index profiles of several fibres are given as an example of its feasibility.
55 citations
TL;DR: In this article, an endlessly single-mode photonic crystal fiber (ESM-PCF) via point-by-point residual stress relaxation utilizing focused CO 2 laser irradiation was used for long-term gratings.
Abstract: We report that the proposed long-period gratings (LPGs), which were fabricated in an endlessly single-mode photonic crystal fiber (ESM-PCF) via point-by-point residual stress relaxation utilizing focused CO 2 laser irradiation, exhibit a high sensitivity to variations in the external refractive index, with an identified shifting of attenuation band as large as 4.4 pm for 1 × 10 −5 change in the surrounding refractive index over the range from 1.42 to 1.45. Contrary to LPGs inscribed in conventional all-solid optical fiber under similar condition, the mode-coupling resonance band of the ESM-PCF-LPG moves towards longer wavelength with increasing refractive index in the surrounding medium of the fiber cladding. The resonance wavelength has a low-temperature coefficient of 2.2 pm/°C over 30–200 °C.
55 citations
TL;DR: In this article, an optimum index profile offering the highest bit rate communication was formed in a poly methyl methacrylate (PMMA)-based graded-index plastic optical fiber (GI-POF) by modifying the polymerization process.
Abstract: An optimum index profile offering the highest bit rate communication was formed in a poly methyl methacrylate (PMMA)-based graded-index plastic optical fiber (GI-POF) by modifying the polymerization process. The interfacial-gel polymerization process we have proposed to fabricate the PMMA-based GI-POF is capable of forming a nearly optimum refractive index profile. However, the theoretically calculated bandwidth from the measured index profile was reduced compared with a GI-POF with an optimum profile. In this paper, we report how to obtain a PMMA-based GI-POF having exactly the optimum index profile. The bandwidth of this ideal GI-POF was experimentally measured and a very high value of 2.88 GHz, even for a 150-m fiber length, was confirmed. The calculated bandwidth agreed well with the experimentally measured one. These results indicate that very low modal dispersion can be expected in a GI-POF fabricated by the modified interfacial-gel polymerization process.
55 citations