Transmission Fiber Chromatic Dispersion Dependence on Temperature: Implications on 40 Gb/s Performance

In this letter, we will evaluate the performance degradation of a 40 km high‐speed (40 Gb/s) optical system, induced by optical fiber variations of the chromatic dispersion induced by temperature changes. The chromatic dispersion temperature sensitivity will be estimated based on the signal quality parameters.     

Advanced modulation formats for more robust optical transmission systems

Interest in advanced modulation formats for optical communication systems has so far experienced two major waves. The first one was motivated by the potential to enhance receiver sensitivity of thermal noise-limited systems using coherent detection in combination with phase shift keying. It ended with the advent of optical amplification, enabling high sensitivities together with polarization insensitive, simple and stable direct detection. The second wave is still rolling, fueled by the potential of advanced modulation formats to increase robustness of optical transmission systems against signal distortions. Due to performance limitations given by direct detection and nonlinear effects in the transmission fiber, it is not decided yet, whether there will be widespread application in carrier networks.     

激光起爆与点火系统中光纤连接器

介绍了激光起爆与点火系统中光纤连接器的原理、种类、技术特性及损耗，并对激光起爆与点火系统中光纤连接器的研制动向进行了概括，最后得出一些结论。     

Ovation DCS控制系统OPC客户端的开发实现

本文主要讨论Ovation DCS控制系统下OPC客户端软件的开发与实现，包括网络结构和软件开发步骤方案等。该方案的实现是实现过程控制的基础，过程控制中数据的交换主要依托该系统方案。它为马钢第三炼铁总厂过程控制系统实现优良性能奠定亍良好的基础。同时也为Ovation DCS控制系统下如何实现过程控制提供了一套解决方案。     

Investigation of structural properties of ITO thin films deposited on different substrates

The influence of the substrate nature on the structure and morphology of ITO thin films grown by thermal evaporation in vacuum is investigated. The as-prepared metal films with Sn/In molar ratio of 0.1 were subsequently annealed for 2 h at 723 K in air (to obtain tin doped indium oxide), then annealed in vacuum at 523 K, followed by UV irradiation (to reduce the electrical resistivity). Irrespective of substrate nature, XRD data evidence a (222) preferential orientation in films. Substrate nature, annealing in vacuum and UV irradiation influence the structure, morphology, optical, electrical and surface wetting properties of the films' surface.     

Unconventional Charge Density Wave Arising from Electron–Phonon Interaction

We report of a theoretical study on quasi-one dimensional unconventional charge density wave (UCDW) driven by electron–phonon interaction. Within mean field theory, we find that the wavevector dependence of the coupling leads to a momentum dependent single particle gap on the Fermi surface. The presence of small energy single particle excitations around the gap nodes significantly changes the optical conductivity compared to the conventional CDW result. In addition to that, the collective phase excitation arising from fluctuation of the order parameter leads to further qualitative changes of the conductivity and results in an effective mass that is nonmonotonic in temperature.      

中国光纤通信技术的研究、应用和发展

主要从光纤光缆、光器件与组件、光传输设备与系统、光网络建设等方面论述光纤通信技术在我国的研究、应用发展历程，并对我国光纤通信技术的未来发展进行展望。     

Chemical compositions and optical properties of HfOxNy thin films at different substrate temperatures

High-k HfO_xN_y thin films have been grown by radio frequency (rf) reactive sputtering of metal Hf target in N₂/Ar/O₂ ambient at different substrate temperatures. The chemical compositions of the films have been investigated as a function of substrate temperature by X-ray photoelectron spectroscopy (XPS). XPS measurements showed that nitrogen concentration increases with an increase in substrate temperature. Room-temperature spectroscopic ellipsometry (SE) with photon energy 0.75–6.5 eV was used to investigate the optical properties of the films. SE results demonstrated that refractive index n increases with an increase in substrate temperature. Based on TL parameters which were obtained from the best fit results used in a simulation of the measured spectra, meanwhile, we conclude that the energy band gap (E_g) decreases with an increase in substrate temperature.     

光纤接入网步入快速发展期

光纤接入一直是多年来人们不断追求的梦想和探索的技术方向，但由于成本、技术、需求等方面的障碍，至今还没有得到大规模推广与发展。然而，这种局面最近有了很大的改观，出现可迅速发展的势头。主要是因为一些国家政策的扶持、运营商竞争的需要、对收入的追求，以及设备本身价格的下降，光纤接入技术由于各种原因，至今尚未在全球广泛应用，但在日本、美国、瑞典和意大利等国都获得了较多的应用。在中国，光纤接入也有了良好的开端，将在大城市广泛应用，并逐渐推广到全国。     

弹性分组环技术

弹性分组环技术是一种新兴的城域网技术。作者主要讨论了弹性分组环技术的特点和优势,并且简要介绍了弹性分组环技术目前在国内城域网建设中的一些应用。弹性分组环技术集以太网的经济性、IP的智能化、光纤环网的丰富带宽和可靠性于一体,是目前宽带IP城域网运营商的最佳组网方案。