Structuring of sapphire by laser-assisted methods, ion-beam implantation, and chemical wet etching

Sapphire is an attractive material for micro- and opto-electronic systems applications because of its excellent mechanical and chemical properties. However, because of its hardness, sapphire is difficult to machine. Titanium-doped sapphire is a well-known broadly tunable and short-pulse laser material and a promising broadband light source for applications in low-coherence interferometry. We investigated several methods to fabricate rib structures in sapphire that can induce channel waveguiding in Ti:sapphire planar waveguides. These methods include direct laser ablation, laser-micromachined polyimide stripes, selective reactive ion etching, and ion-beam implantation followed by chemical wet etching. Depending on the method, we fabricated channels with depths of up to 1.5 µm. We will discuss and compare these methods. Reactive ion etching through laser-structured polyimide contact-masks has so far provided the best results in terms of etching speed and roughness of the etched structures

Транспортная логистика: проблемы и перспективы развития в таможенном деле

Выпускная квалификационная работа посвящена исследованию транспортной логистике в таможенном деле. Целью данной работы является комплексный анализ факторов, механизмов и проблем трансформации таможенной логистики в глобальной торговой системе и обоснование направлений адаптации таможенной логистики России в условиях либерализации международной торговли. Задачи: •Понятие, виды, функции логистики •Задачи транспортной логистики •Сущность таможенной логистики •Проблемы становления таможенной логистики •Ключевые проблемы таможенной логистики •Перспективы развития таможенной логистики. Объектом исследования является процесс формирования и реализации таможенной логистики в глобальной торговой системе.The final qualifying work is devoted to the study of transport logistics in the customs business. The purpose of this work is a comprehensive analysis of the factors, mechanisms and problems of the transformation of customs logistics in the global trading system and the rationale for adapting the customs logistics of Russia in the context of the liberalization of international trade

Structural and electrical transport properties of superconducting Au{0.7}In{0.3} films: A random array of superconductor-normal metal-superconductor (SNS) Josephson junctions

The structural and superconducting properties of Au{0.7}In{0.3} films, grown by interdiffusion of alternating Au and In layers, have been studied. The films were found to consist of a uniform solid solution of Au{0.9}In{0.1}, with excess In precipitated in the form of In-rich grains of various Au-In phases (with distinct atomic compositions), including intermetallic compounds. As the temperature was lowered, these individual grains became superconducting at a particular transition temperature (Tc), determined primarily by the atomic composition of the grain, before a fully superconducting state of zero resistance was established. From the observed onset Tc, it was inferred that up to three different superconducting phases could have formed in these Au{0.7}In{0.3} films, all of which were embedded in a uniform Au{0.9}In{0.1} matrix. Among these phases, the Tc of a particular one, 0.8 K, is higher than any previously reported for the Au-In system. The electrical transport properties were studied down to low temperatures. The transport results were found to be well correlated with those of the structural studies. The present work suggests that Au{0.7}In{0.3} can be modeled as a random array of superconductor-normal metal-superconductor (SNS) Josephson junctions. The effect of disorder and the nature of the superconducting transition in these Au{0.7}In{0.3} films are discussed.Comment: 8 text pages, 10 figures in one separate PDF file, submitted to PR

Erbium ion implantation doping of opto-electronic materials operating at 1.5 mu m

Soda-lime silicate and Al/sub 2/O/sub 3/ waveguide films, LiNbO/sub 3/ single crystal, as well as crystal Si are doped with erbium by ion implantation. All materials show luminescence at 1.5 mu m, characteristic for Er, with lifetimes up to 12 m

Peter Grünberg - Nobelpreis für Physik 2007

The year 2007 was a particularly important year for Forschungszentrum Jülich and Prof. Peter Grünberg. With this book, we not only want to honour Grünberg but also to thank him for his discoveries, which he made here in Jülich. What was to become known as the giant magnetoresistance effect (GMR effect) was discovered by Grünberg in 1988 within the framework of basic research on magnetism. A read head for hard disk drives based on this discovery quickly conquered the world of industrial applications. Since 1997, the GMR effect has been used almost exclusively to read out information stored magnetically on hard drives. With more than fi ve billion read heads produced to date, statistically there is one GMR sensor for almost every member of the human race. We use this quantum-mechanical physical effect every day in computers or hard drive recorders without even realising it. What we are aware of is the rapid development of magnetic data storage, which is continuously opening the way for new applications. The storage capacity of hard drives has increased substantially thanks to GMR read heads and has reached 1 terabyte today. This development is set to continue. In the future, we will be using even smaller electronic devices that will be able to deal with even larger amounts of data in even shorter periods of time with a lower energy demand...