····· lezzter Preis 32.30€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Spin-sensitive low temperature Scanning Tunneling Microscopy (STM) measurements provide the unique capability to study structural, electronic and magnetic properties of individual and coupled magnetic atoms on surfaces with high energy resolution. In this thesis, spin-polarized STM (SP-STM) and Inelastic Scanning Tunneling Spectroscopy (ISTS) are utilized to investigate Fe atoms on the semiconducting InSb(110) surface and the metallic Cu(111) and Ag(111) surfaces. Model calculations of tunneling through an excitable quantum spin system and analytical investigations of the model, as well as quasi-classical and Ising model calculations of coupled spin systems prepare the ground for the theoretical description of the experiments. The ISTS measurements of Fe on InSb(110) are the first observation of spin excitations of individual magnetic atoms on a semiconductor surface. By comparing the experimental data to Density Functional Theory (DFT) calculations performed by S. Schuwalow and F. Lechermann and to model calculations, it is found that the Fe atoms behave like quantum spins with spin quantum number S = 1, which are subject to magnetic anisotropy in the meV range. The Fe atoms are coupled to a two dimensional electron system (2DES) which is induced at the surface by positively charged adsorbates. The spectroscopic peaks of the spin-split Landau levels of this 2DES show an asymmetry of their amplitudes when the tunnel current is passed through the Fe atoms. It is shown that the Landau level asymmetry, recorded as a function of external magnetic field, can be interpreted as a new type of Single Atom Magnetization Curve (SAMC). Measurements of the Landau level asymmetry with magnetic tips can be used to quantitatively determine the spin polarization of the tip. SP-STM measurements of the SAMCs of single Fe atoms on Cu(111) show that the Fe atoms behave paramagnetically with a broad statistical distribution of the effective magnetic moment, centered around 3.5 µB. ISTS measurements on the same system reveal a magnetic anisotropy energy in the meV range, a g-factor of about 2.1, and a very broad, energy dependent spin-excitation line width in the meV range. Analogous ISTS measurements of Fe on Ag(111) show similar behavior, but with a three times larger anisotropy energy, and a g-factor of roughly 3.1. The observations can be interpreted in the context of advanced calculations including spin-orbit coupling and the Cu/Ag(111) surface state performed by S. Lounis et al..Atomic manipulation is used to construct pairs, chains and other structures of coupled Fe atoms on Cu(111). Their magnetization and coupling behavior is studied with the SAMC technique using spin-polarized tips and compared to Ising model calculations. The extracted RKKY pair coupling as a function of pair separation shows deviations from the isotropic case. The larger structures behave approximately as expected from the measured pair couplings, with deviations for small external magnetic fields. Even and odd numbered antiferromagnetically coupled chains show distinctly different magnetic ground states. A model type spin logic OR gate is constructed by connecting an Fe ¿output` atom by magnetically coupled Fe chains to two ferromagnetic ¿input` Co nanoislands. The functionality of the OR gate is demonstrated experimentally, constituting the first operation of an atomic spin logic function in this kind of magnetic nanostructure. Ising model calculations complement the experiments. ····· 10361193077
····· lezzter Preis 25.27€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In this work scanning probe techniques, namely frequency-modulated atomic force microscopy (FM-AFM) in the non-contact regime and related methods like Kelvin probe force microscopy (KPFM), magnetic force microscopy (MFM), and magnetic exchange force microscopy (MExFM), are utilized in ultra high vacuum and at low temperatures to structurally, electronically and magnetically study the monolayer regime of iron on tungsten (001) in real space. Implementing the spectroscopic mode of MExFM, that is, magnetic exchange force spectroscopy (MExFS), the exchange interaction between single iron atoms with antiparallel coupling is experimentally accessed for the rst time. Iron grows pseudomorphically on W(001) whereby the layers are highly strained. Di erences in strain between rst and second layer iron and hybridization with the substrate lead to di erences in electronic properties and magnetism: both layers exhibit a di erent work function, mapped with KPFM. Interestingly, even on the same layer, di erent work functions are observed. Moreover, both layers are magnetically di erent. The second layer is ferromagnetic (FM) with in-plane anisotropy as veri ed by MFM, while the rst layer is antiferromagnetic (AF) with out-of-plane anisotropy. Using MexFM the AF alignment of the monolayer magnetic moments is resolved by detecting the short-ranged magnetic exchange force between tip and sample. The origin of the magnetic contrast formation is discussed and compared to ab initio calculations. Later, MExFS, which allows to directly measure the distance dependence of the magnetic exchange interaction between an atomically sharp magnetic tip and the antiferromagnetically ordered Fe monolayer on W(001), is employed. The site speci c distance dependence of the total tip-sample interaction is recorded above Fe atoms which exhibit parallel as well as antiparallel atomic magnetic moments. The contribution of the magnetic exchange interaction between both sites can be extracted by subtracting the two curves from each other. All other interactions are identical on both sites. The experimental results are compared to ab initio calculations accounting for magnetically di erent tips composed of either Cr or Fe, or mixtures of both. Depending on symmetry and stability of the experimentally used probe tips, qualitatively di erent MExFM contrasts and MExFS data with a stronger distance dependence are observed. By analyzing the energy loss per single cantilever oscillation cycle, simultaneously recorded with topography and frequency shift in the experiments, a bottom-up characterization of the structurally and magnetically unknown probe tip apex is given. Considering the tip apex as magnetically and structurally independent cluster allows to explain the observed tip behavior. ····· 10361193075
····· lezzter Preis 17.10€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Fluoridglas eignet sich aufgrund seiner hohen Transparenz vom ultravioletten bis zum nahinfraroten Spektralbereich sowie der geringen Phononenenergien außerordentlich gut für Anwendungen im sichtbaren Spektralbereich. Als Wirtsmaterial kann es große Mengen an Seltenerdionen als Dotierung aufnehmen. Erbiumdotiertes ZBLAN zeigt bei Anregung mit Wellenlängen von 970 - 980 nm starke grüne Fluoreszenz, welche durch die schrittweise Absorption von zwei Photonen in einem Aufwärtskonversionsprozess in den langlebigen angeregten Zustand 4S3/2 erfolgt. Die genaue Analyse der thermischen Eigenschaften vom Fluoridglas ZBLAN und weiteren Gläsern, welche entweder einen gewissen Bleianteil oder einen Hafniumanteil aufweisen, gibt Aufschluss über Glasstabilität, Wärmeausdehnung und charakteristische Temperaturen. Die Refraktometrie und Ellipsometrie zeigen, in welchem Maße der Brechungsindex durch Blei- und Hafniumanteile variiert werden kann. Diese Informationen sind nicht zuletzt hilfreich für die Wahl eines passenden Substratmaterials, welche auf CaF2 fiel. Das modifizierte Spin-Coating-Verfahren hat sich als eine erfolgreiche Methode erwiesen, um dämpfungsarme Glasfilme mit sehr glatter Oberfläche aus Fluoridglas herzustellen. Die Glasfilme können mit beliebigen Seltenerdionen in unterschiedlichen Konzentrationen dotiert werden. Dabei sind die Fluoreszenzspektren von erbiumdotierten Glasstücken und Filmen im grünen Spektralbereich vergleichbar. Mit Fotolithografie und anschließendem nasschemischen Ätzprozess gelingt die Strukturierung der Filme zu Streifenwellenleitern. Anhand von Mikroskopaufnahmen IR-gepumpter und fluoreszierender Streifenwellenleiter sind keine Streuverluste an den strukturierten Kanten sichtbar, so dass die durch das Ätzen zusätzlich eingebrachten Verluste gering sind. Die hergestellten erbiumdotierten Streifenwellenleiter aus Fluoridglas besitzen Querschnitte zwischen 40 x 40 µm2 und 40 x 230 µm2 und zeigen Wellenführung. In einer Simulation wurde gezeigt, dass ein IR-gepumpter, effizienter grüner Wellenleiterlaser realisierbar ist, jedoch hohe Pumpleistungen benötigt, um die Laserschwelle zu erreichen. Die Kombination mehrerer Ansätze sollte jedoch zum Erfolg führen: Zum einen kann eine Kodotierung mit Ytterbium die Pumpabsorption verbessern. Desweiteren führt ein kleinerer Wellenleiterquerschnitt bei guter Fokussierung und Einkopplung des Pumplasers in den Wellenleiter zu höheren Intensitäten im Resonator. Kleinere Wellenleiterquerschnitte werden durch dünnere Schichten erreicht, welche ihrerseits durch das Aufbringen einer Deckschicht aus Fluoridglas erzielt werden. Optische und thermische Eigenschaften von erbiumdotiertem ZBLAN in Kombination mit weiter optimierten Methoden zur Herstellung von verlustarmenWellenleitern werden in absehbarer Zukunft zur Realisierung einer kompakten grünen Laserquelle führen. ····· 10361192688
····· lezzter Preis 49.95€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Physik gilt nach wie vor als wichtigste Grundlage für eine ganze Reihe von Wissenschaften von den Natur- über die Technik- bis zu den Ingenieurwissenschaften. Giancoli Physik, der Lehrbuchklassiker zur Physik, wendet sich mit dieser Ausgabe an Schüler, die in der Oberstufe des Gymnasiums das Fach Physik in einem Grund- oder Leistungskurs gewählt haben. Es ist eine gekürzte Fassung des Lehrbuchs, das langjährig in der Lehre weltweit etabliert und für seine Verständlichkeit wie auch die lebendige Präsentation des Stoffes berühmt ist. Die vorliegende Ausgabe für die gymnasiale Oberstufe behält diese Merkmale und gibt einen umfassenden Überblick über die Physik - allerdings mit Schwerpunkt auf den wichtigen Themen der gymnasialen Oberstufe und mit einer reduzierten mathematischen Komplexität. Jedes Kapitel bietet viele durchgerechnete Beispiele, zusätzliche Aufgaben und Lösungen sowie eine Zusammenfassung des jeweiligen Fachgebietes. Besonders nützlich zur Abitur- und Klausurvorbereitung sind zudem die ausführlichen Lösungswege auf der Companion Website zu den zahlreichen Übungen im Buch. Dies alles zusammen macht dieses Schulbuch zum idealen Begleiter für Schüler, die ihr Verständnis der Physik mit ausführlichen Erklärungen vertiefen und an anspruchsvollen Aufgaben überprüfen wollen. Mit enthalten ist ein Zugangscode für MyMathLab | Brückenkurs (Nutzungsdauer 12 Monate). Damit kann der Schüler oder der Studierende gezielt mathematische Fähigkeiten, die für die Physik nötig sind, sich aneignen.
····· lezzter Preis 24.95€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Statistische Methoden in der Experimentalphysik In der Physik haben Datenanalysen zentrale Bedeutung für die Bewertung von experimentellen Resultaten. Dieses Lehrbuch startet mit den elementaren Konzepten der Statistik, zeigt die wichtigsten Wahrscheinlichkeitsverteilungen und erklärt die Datenanalysemethoden für Experimente der Laborpraktika. Darüber hinaus werden Konzepte moderner wissenschaftlicher Datenanalysen von der Computer-Simulation bis zur Klassifizierung mit neuronalen Netzwerken vorgestellt. ····· 10361185263
····· lezzter Preis 43.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Der Mensch definiert die funktionalen Anforderungen an Lichtsysteme im Automobil. So stellt sich mit der Integration neuer Konzepte im Fahrzeug vor allem die Frage nach deren Einfluss auf die Wahrnehmungsleistung des Fahrers. Daher bildet die physiologisch-psychologische Bewertung von Lichtfunktionen ein wichtiges Glied in der Entwicklungskette lichttechnischer Komponenten. Im Rahmen der vorliegenden Arbeit werden ausgewählte Systeme im In- und Exterieurbereich psychophysikalisch analysiert. ····· 10361164612
····· lezzter Preis 45.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The linear and nonlinear resonance behaviour of optical antennas (metallic nanostructures showing resonance behaviour at optical frequencies) made of gold and aluminum using electron-beam lithography is investigated. Specifically, it is of interest how the emission behaviour is changed by the coupling of two antenna arms via a small gap. Experimental techniques applied include dark-field spectroscopy and two-photon luminescence. ····· 10361164476
····· lezzter Preis 46.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Diese Arbeit befasst sich mit verschiedenen nano- und mikrotechnologischen Konzepten zur Steigerung der Auskoppeleffizienz von OLEDs.Hierfür werden drei bottom-up-Ansätze, bei denen Nanopartikel während der OLED-Herstellung in die OLED eingebracht werden, beschrieben und zwei top-down-Ansätze vorgestellt, bei denen vor der eigentlichen OLED-Herstellung die Substratoberfläche durch Nano- und Mikrostrukturierung modifiziert wird. ····· 10361164440
····· lezzter Preis 43.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In this work two ideas of using individual metal organic molecules in applications for data storage are presented. On the one hand, metal-free phthalocyanine is used to form a GMR contact consisting of one single molecule leading to the world smallest magnetic sensor. On the other hand, chromium acetylacetonate was used to study the properties of magnetic molecules adsorbed on surfaces in order to build magnetic bits for date storage. ····· 10361164427
····· lezzter Preis 31.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book discusses design, modeling, and the characterization of slow-light photonic crystal waveguides. Guidelines are developed to obtain slow-light waveguides with broadband characteristics and with low disorder-induced losses. Three functional devices are proposed and studied: A tunable dispersion compensator, a tunable optical delay line, and a high-speed electro-optic modulator. Optical and microwave measurements confirm the designs. ····· 10361164339
····· lezzter Preis 58.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Durch die Zusammenführung der Traditionen von Mathematik und Physik gilt der deutsche Physiker Franz Ernst Neumann (1798-1895) als Begründer der theoretischen Physik.Er war Professor für Mineralogie und Physik und später Rektor an der Universität Königsberg. Dort schloss er auch Freundschaft mit dem Astronom Friedrich Wilhelm Bessel und dem Naturwissenschaftler Karl Gottfried Hagen.Zu Neumanns zentralen Forschungsthemen gehören vor allem die Kristallographie, die spezifische Wärme, die Wellentheorie des Lichts, der Elektromagnetismus sowie mathematische Methoden in der Physik. ····· 10361159280
····· lezzter Preis 62.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Der schottische Physiker James Clark Maxwell (1831-1879) gilt als der Naturwissenschaftler des 19. Jahrhunderts mit dem größten Einfluss auf die theoretische und experimentelle Physik des 20. Jahrhunderts.JamesClark Maxwell studierte Naturphilosophie, Moralphilosophie und Mentale Philosophie sowie Mathematik und Physik. Zu seinen Lehrern gehörte Sir William Hamilton.Seine Ausarbeitungen über elektronmagnetische Gleichungen vollendete Maxwell noch zu Studienzeiten. Sie bilden heute die Grundlage der modernen Elektrizitätslehre und des Magnetismus. Die von ihm entdeckte Maxwellverteilung behandelt die Geschwindigkeitsverteilung von Gasmolekülen.Maxwell war ab 1856 Professor für Naturphilosophie in Aberdeen, bevor an den Lehrstuhl für Physik und Astronomie am King`s College in London berufen wurde. Im Jahre 1871 wurde er erster Cavendish-Professor für Experimentalphysik in Cambridge. ····· 10361159279
····· lezzter Preis 49.90€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Joseph John Thomson erhielt 1906 den Nobelpreis für Physik. Er war Entdecker des Elektrons. Nachdruck des Originals von 1909. ····· ····· ····· ····· ····· ····· ····· ····· ····· 10361150821
····· lezzter Preis 19.90€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Joseph John Thomson erhielt 1906 den Nobelpreis für Physik. Er war Entdecker des Elektrons. Nachdruck des Originals von 1909. ····· ····· ····· ····· ····· ····· ····· ····· ····· 10361150806
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The purpose of this book is to study the transmitting of the optical signal (laser) via optical fibers to reach long distances about 600km and find suitable solutions to fix the problems of attenuation and dispersion and possibility of using optical regenerators which were used as an alternative to traditional ways (electronic regenerators) and showing the benefits of using optical regenerators. Virtual photonics programs have been used to find simulation to optical systems in order to represent special modules for research A dense wavelength division multiplexing was described, whereas 64 channels have been amplified at the same time and was obtain (constant signal output) without going to use automatic gain control. Also a preamplifier module was studied including optical pumping, amplifier length and the effect on gain and noise. ····· 10361147244
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The most important element in lightning protection system is grounding. A good grounding system is a system that dissipates the lightning current into the ground efficiently. For designing optimal and effective grounding systems better understanding of the behavior of grounding systems under transient currents is essential. An optimal design is important for achieving Electromagnetic Compatibility (EMC) requirements as well as protection against high currents and voltage hazards. In this work, a model for calculating the response of a vertical electrode to lightning current is presented. The model is based on electromagnetic field theory, which is the most rigorous method for approaching the problem. The model takes into account the radius of the electrode, the conductivity and permittivity of the ground. ····· 10361147131
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In recent years there has been a substantial increase in the demand for controllable reactive power sources which can compensate for large lagging loads. These requirements involve precise and continuous reactive power control with fast response time and avoidance of harmonic line current generation. Solid state Var compensators using forced commutated converters have been developed and are being used for this purpose. Active power filtering (APF) can provide VAr compensation by injecting equal but opposite distortion at selected points in a network. The objective of this project is to design an Active Power Filter (APF) using Voltage Source Inverter (VSI) to achieve reactive power compensation. It is achieved by forcing the inverter line current to follow a reactive sinusoidal reference at a constant switching frequency. The current reference generator has been designed for both lagging and leading reactive power conditions. The reactive power requirements of a bridge rectifier connected load are estimated using the above current reference generator. Using this, an APF is designed to compensate the reactive power requirements of the above load. ····· 10361147104
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In this research, we characterized magnetic and electromagnetic interferences of a two-stage pulse tube cryocooler to a LTc SQUID attached directly to the cold stage of the cryocooler and found the noise sources and proposed methods to reduce their interference on the operation of the LTc SQUID. In chapter one an introduction to cryocoolers and cryocooler based SQUID systems is given. Chapter two presents our method to measure the conducted high frequency electromagnetic interference into the cryocooler cold head via noise paths. In chapter three characterization of low frequency magnetic noises of a two-stage pulse tube cryocooler is presented. Because of the similarity of the profile of the magnetic noise during cool down process with that of the temperature variation we attributed a main noise source to the presence of magnetic regenerative materials located in the second stage. Finally a superconducting lead shield covering over the section containing magnetic regenerative materials at the second stage is proposed to reduce the interference of the noise to the SQUID attached directly on the second stage cold head. ····· 10361146793
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The study of energy propagation and localization in optical lattices has become an important subject of research in several areas of science including mathematical physics, nonlinear optics and Bose-Einstein condensates. This book presents an original theoretical, numerical and experimental investigation of energy dynamics in nonlinear optical lattices. Theoretical work discusses nonlinear waves in both paraxial and nonparaxial regimes, the generation of solitons through nonlinear defects, the use of Lie groups in the study of universality of physical models and finally accelerated lattices with applications to dispersion spectroscopy. The numerical part consists in the realization of a nonlinear code to simulate light propagation in nematic liquid crystals, the latter being the material chosen for the experimental side of the work. Finally, experiments with voltage-driven nematic liquid crystals demonstrates tunable discrete diffraction, discrete solitons and their angular steering, multi-gap breathers and light driven Landau-Zener tunneling. The work discussed by this book led to the publication of 26 articles in peer-reviewed journals and 28 international conferences. ····· 10361146673
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Nowadays power drives are the essential part almost of all technological processes. Improvement of efficiency and reduction of losses require development of semiconductor switches. It has a particular meaning for the constantly growing market of renewable sources, especially for wind turbines, which demand more powerful semiconductor devices for control, while power of turbines constantly grows. Also at present semiconductor switches are the key component in energy transmission, optimization of generation and network connection. The aim of this book is to make a survey of contemporary semiconductor components, showing difference in structures, advantages, disadvantages and most suitable applications. There is topical information about voltage, frequency and current limits of different switches. The book also tells about future prospects of semiconductor market. ····· 10361146612
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The reconfiguration process for Shipboard Power System reroutes the electric power in the power system in order to achieve certain objectives, The reconfiguration process can improve the survivability and reliability of the power system. Most of today`s reconfiguration methodologies are centralized. In a Shipboard Power System s centralized reconfiguration approach, a single point of failure may happen if the system lacks redundancy. The Multi Agent System (MAS) technology is recently applied to the applications in power systems. The MAS is composed of agents that are intelligent entities with the capability of problem solving. However, current MAS applications on power system reconfiguration methodologies are topology dependent. Additionally, No MAS based reconfiguration methodology has been proposed for mesh structured power system reconfiguration.In this book, a completely decentralized MAS based reconfiguration methodology is proposed for Shipboard Power Systems. In this approach, an MAS is proposed for the reasoning of the reconfiguration. Each agent works autonomously and independently and the MAS works in a completely decentralized manner. ····· 10361146572
····· lezzter Preis 59.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray An experiment and theoretical analysis have been done to measure the nonlinear refractive index n2 of LiNbO3 for different three wavelengths laser light of a continuous Ar-ion laser and observe the variation of the value and sign of the nonlinear refractive index. The Z-scan is a simple technique for measuring the change in phase induced on a laser beam upon propagation through a nonlinear material. It gives both the sign and magnitude of this phase change , which is simply related to the change in index of refraction, . For different wavelength the sign and the value of index of refraction is different. Additionally, for third-order nonlinear responses the real part of the third-order nonlinear susceptibility, , can be measured. However, Z- scan is sensitive to any nonlinear processes which results in , so that great care must be taken in interpreting data taken with this or any other nonlinear materials characterization technique. ····· 10361146395
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Reactive compensation in distribution networks is a typical optimization problem of great technical and economic importance, which has been faced over five decades. It consists of determining installation points and operation control program of a certain number of capacitor banks in order to maximize the profits obtained from system losses reduction. The extent of the benefits from capacitor banks installation depends on electrical network configuration and its load states. Therefore, on this book, a great deal of attention has been focused on introducing methods to determine the size and location of shunt capacitor banks on distribution systems. The primary objective of this book is not based only on introducing new strategies but also to introduce and study the application of fuzzy set theory (FST) to the capacitor allocation problem. In addition, two methods are proposed in this book to study the impact of harmonics, which may exist in the distribution system on the capacitor allocation problem. ····· 10361146292· 1 ·· 2 ·· 3 ·· 4 ·· 5 ·· 6 ·· 7 ·· 8 ·· 9 ·
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