This book presents the latest advances in ultrafast science, including ultrafast laser and measurement technology as well as studies of ultrafast phenomena. Pico- and femtosecond processes relevant in physics, chemistry, biology and engineering are presented. Ultrafast technology has had a profound impact in a wide range of applications, among them imaging, material diagnostics and transformation and high-speed optoelectronics. This book summarizes the results presented at the 12th Ultrafast Phenomena Conference and reviews the state of the art of this important and rapidly advancing field.

Laser-Beam Interactions with Materials treats, from a physicist's point of view, the wide variety of processes that lasers can induce in materials. Physical phenomena ranging from optics to shock waves are discussed, as are applications in such diverse fields as semiconductor annealing, hole drilling and fusion plasma production. The approach taken emphasizes the fundamental ideas and their interrelations. The newcomer is given the necessary important background material, while the active research worker finds a critical and comprehensive review of the field.

Plasma Atomic Physics provides an overview of the elementary processes within atoms and ions in plasmas, and introduces readers to the language of atomic spectra and light emission, allowing them to explore the various and fascinating radiative properties of matter. The book familiarizes readers with the complex quantum-mechanical descriptions of electromagnetic and collisional processes, while also developing a number of effective qualitative models that will allow them to obtain adequately comprehensive descriptions of collisional-radiative processes in dense plasmas, dielectronic satellite emissions and autoionizing states, hollow ion X-ray emissions, polarized atoms and ions, hot electrons, charge exchange, atomic population kinetics, and radiation transport. Numerous applications to plasma spectroscopy and experimental data are presented, which concern magnetic confinement fusion, inertial fusion, laser-produced plasmas, and X-ray free-electron lasers' interaction with matter. Particular highlights include the development of quantum kinetics to a level surpassing the almost exclusively used quasi-classical approach in atomic population kinetics, the introduction of the recently developed Quantum-F-Matrix-Theory (QFMT) to study the impact of plasma microfields on atomic populations, and the Enrico Fermi equivalent photon method to develop the "Plasma Atom", where the response properties and oscillator strength distribution are represented with the help of a local plasma frequency of the atomic electron density. Based on courses held by the authors, this material will assist students and scientists studying the complex processes within atoms and ions in different kinds of plasmas by developing relatively simple but highly effective models. Considerable attention is paid to a number of qualitative models that deliver physical transparency, while extensive tables and formulas promote the practical and useful application of complex theories and provide effective tools for non-specialist readers.

1 Basic Laser Mechanisms.- 2 Optics, Resonators and Beams.- 3 Carbon Dioxide Lasers.- 4 Solid State Lasers.- 5 Excimer Lasers.- 6 Semiconductor Lasers.- 7 Safety.- 8 Beam Manipulation.

The book explains the classification of a set of Walsh functions into distinct self-similar groups and subgroups, where the members of each subgroup possess distinct self-similar structures. The observations on self-similarity presented provide valuable clues to tackling the inverse problem of synthesis of phase filters. Self-similarity is observed in the far-field diffraction patterns of the corresponding self-similar filters. Walsh functions form a closed set of orthogonal functions over a prespecified interval, each function taking merely one constant value (either +1 or 1) in each of a finite number of subintervals into which the entire interval is divided. The order of a Walsh function is equal to the number of zero crossings within the interval. Walsh functions are extensively used in communication theory and microwave engineering, as well as in the field of digital signal processing. Walsh filters, derived from the Walsh functions, have opened up new vistas. They take on values, either 0 or phase, corresponding to +1 or -1 of the Walsh function value.

A Comprehensive overview of the theory and applications of laser welding

This complete and up-to-date overview examines both the state of the art and likely future directions of laser welding technology. Paying particular attention to manufacturing, where applications of laser welding range from vehicle assembly to the joining of microelectric components, this comprehensive volume reviews the fundamentals, examines the latest research data, and offers detailed coverage of practical applications. The emphasis is on optimizing laser welding techniques to achieve defect-free results at high speed and under reproducible conditions. Author Walter W. Duley also discusses design issues, material properties, and the efficient delivery of laser radiation in welding applications, as well as the practical aspects of joint design. Other important features of this book include:

• Comprehensive data on real-world laser welding applications, including the new application of tailor blanking
• Performance criteria for numerous laser welding systems
• A review of available welding data for various metals and other materials
• A section on laser welding diagnostics and monitoring techniques
• Over 160 illustrations
• Extensive references and a bibliography for specific industrial applications.

Laser Welding is an indispensable resource for engineers and scientists using laser welding technology and a useful text for students in physics, material science, and mechanical engineering. It is also a valuable reference for researchers and designers developing new laser welding systems and studying the laser welding process. Walter W. Duley is a professor at the University of Waterloo in Ontario, Canada, and is the founder and former chairman of Powerlasers Limited. His previous books include UV Lasers: Effects and Applications in Materials Science, Laser Processing and Analysis of Materials, and CO2 Lasers: Effects and Applications.

Readers will learn in which ways light can be "confined" within a subwavelength region smaller than half a wavelength. Strictly within the focal spot, all degrees of freedom of light interact and manifest themselves in a dramatic way. The size and shape of the focal spot and the magnitude of side-lobes depend on the polarization state alongside phase and amplitude distributions of a light beam. Readers will learn techniques in which inhomogeneously (i.e., azimuthally and radially) polarized optical beams can be focused. In sharp focus, exotic phenomena can occur, including the negative propagation of light and a toroidal optical flow. Throughout the book, the numerical simulation is performed using the rigorous solution of Maxwell's equations based on a Finite-Difference Time-Domain (FDTD) approach, which makes the results of modeling highly reliable. The photonic components, including optical metasurfaces, discussed in the book have been implemented using state-of-the-art techniques of electron beam writing and reactive ion-beam etching of microrelief. Two chapters are concerned with photonics hot spots, which deal with the control of light by means of optical metasurfaces and the generation of an energy backflow in the region of sharp focus of a laser beam. Another hot topic is diffractive polarization converters implemented as subwavelength diffraction gratings to convert polarization of light. By way of illustration, such converters are shown to perform linear-to-radial or linear-to-azimuthal polarization conversion. The book describes advanced photonic components fabricated by the authors to perform sharp focusing of light, including binary zone plates, binary axicons, a planar photonic crystal lens, diffraction polarization converters, and metalenses. This book is a must-have for individuals and institutions studying cutting edge optics.

Metallic quantum clusters belonging to intermediate size regime between two and few hundred of atoms, represent unique building blocks of new materials. Nonlinear optical (NLO) characteristics of liganded silver and gold quantum clusters reveal remarkable features which can be tuned by size, structure and composition. The two-photon absorption cross sections of liganded noble metal quantum clusters are several orders of magnitude larger than that of commercially-available dyes. Therefore, the fundamental photophysical understanding of those two-photon processes in liganded clusters with few metal atoms deserve special attention, in particularly in context of finding the mechanisms responsible for these properties. A broad range of state-of-the-art experimental methods to determine nonlinear optical properties (i.e. two-photon absorption, two-photon excited fluorescence and second harmonic generation) of quantum clusters are presented. The experimental setup and underlying physical concepts are described. Furthermore, the theoretical models and corresponding approaches are used allowing to explain the experimental observations and simultaneously offering the possibility to deduce the key factors necessary to design new classes of nanoclusters with large NLO properties. Additionally, selected studied cases of liganded silver and gold quantum clusters with focus on their NLO properties will be presented as promising candidates for applications in imaging techniques such as fluorescence microscopy or Second-Harmonic Generation microscopy.

The propagation of light in 'dense media' where dipole-dipole interactions play a role is a fundamental topic that was first studied in the work of Clausius, Mossotti, Lorenz and Lorentz in the latter half of the nineteenth century. However, until recently there remained some areas of controversy: for example, whereas the Lorentz model for a gas predicts a resonance shift, a discrete dipole model does not. This thesis makes the first combined measurement of both the Lorentz shift and the associated collective Lamb shift. This clear experimental result stimulated new theoretical work that has significantly advanced our understanding of light propagation in interacting media.

This textbook provides a thorough and accessible treatment of semiconductor lasers from a design and engineering perspective. It includes both the physics of devices as well as the engineering, designing and testing of practical lasers. The material is presented clearly with many examples provided. Readers of the book will come to understand the finer aspects of the theory, design, fabrication and test of these devices and have an excellent background for further study of optoelectronics. This book also: Provides a multi-faceted approach to explaining the theories behind semiconductor lasers, utilizing mathematical examples, illustrations and written theoretical presentations Offers a balance of relevant optoelectronic topics, with specific attention given to distributed feedback lasers, growth techniques and waveguide cavity design Provides a summary of every chapter, worked examples, and problems for readers to solve Incorporates and explains recent breakthroughs in laser design

A state of the art presentation of important advances in the field of digital holography, detailing advances related to fundamentals of digital holography, in-line holography applied to fluid mechanics, digital color holography, digital holographic microscopy, infrared holography, special techniques in full field vibrometry and inverse problems in digital holography

This book focuses on the recent progress in nanophotonics technology to be used to develop novel nano-optical devices, fabrication technology and advanced systems. It reviews light-emitting diodes and lasers made of silicon bulk crystals in which the light emission principle is based on dressed-photon-phonons. Further topics include: theoretical studies of optoelectronic properties of molecular condensates for organic solar cells and light-emitting devices, the basics of topological light beams together with their important properties for laser spectroscopy, spatially localized modes emerging in nonlinear discrete dynamic systems and theoretical methods to explore the dynamics of nanoparticles by the light-induced force of tailored light fields under thermal fluctuations. These topics are reviewed by leading scientists. This overview is a variable resource for engineers and scientists working in the field of nanophotonics.

In continuation of the FRINGE Workshop Series this Proceeding contains all contributions presented at the 7. International Workshop on Advanced Optical Imaging and Metrology. The FRINGE Workshop Series is dedicated to the presentation, discussion and dissemination of recent results in Optical Imaging and Metrology. Topics of particular interest for the 7. Workshop are: - New methods and tools for the generation, acquisition, processing, and evaluation of data in Optical Imaging and Metrology (digital wavefront engineering, computational imaging, model-based reconstruction, compressed sensing, inverse problems solution) - Application-driven technologies in Optical Imaging and Metrology (high-resolution, adaptive, active, robust, reliable, flexible, in-line, real-time) - High-dynamic range solutions in Optical Imaging and Metrology (from macro to nano) - Hybrid technologies in Optical Imaging and Metrology (hybrid optics, sensor and data fusion, model-based solutions, multimodality) - New optical sensors, imaging and measurement systems (integrated, miniaturized, in-line, real-time, traceable, remote) Special emphasis is put on new strategies, taking into account the active combination of physical modeling, computer aided simulation and experimental data acquisition. In particular attention is directed towards new approaches for the extension of existing resolution limits that open the gates to wide-scale metrology, ranging from macro to nano, by considering dynamic changes and using advanced optical imaging and sensor systems.

For most elements of the periodic table, reliable computations of atomic data and properties are still a challenge for (atomic) theory today. Despite of the great effort, that has been undertaken by many groups worldwide during the past four decades, yet serious difficulties arise not only from the complexity of most atoms and ions but also from the large variety of data that is needed in different fields of physics and science. In practice, one often faces several intricacies in performing such computations with the largest, perhaps, (1) due to the shell structure of most atoms and ions. This shell structure, i. e. the occupation of the atomic subshells, does not only change typically when an atom undergoes some transition but also hampers the analysis of one and the same property between neighboured elements. In fact, the particular shell structure of an atom or ion strongly affects the number of degenerate levels (or those nearby in energy) and may thus lead to very different computational requirements in dependence of the occupation of the shells. Further difficulties arise in addition also from (2) the relativistic treatment on the basis of the Dirac-Coulomb (-Breit) Hamiltonian (which is needed for most medium and heavy elements, and sometimes even for the light ones) as well as from (3) the fact that many atomic properties are accompanied by the capture or emission of free electrons.

Nonlinear optical (NLO) phenomena such as frequency conversion have played a key role in the development of photonic technologies. This thesis reports a detailed study of the molecular response of a large variety of push-pull organic compounds using the Second Harmonic Generation technique, which will serve as a starting point for the investigation at the macroscopic scale of azobenzene-based liquid crystalline polymeric films and their blends with highly efficient NLO chromophores. These materials are designed with the aim of exploiting their photoadressability in order to tailor their nonlinear behaviour. The magnitude and symmetry of their NL response was successfully controlled via light irradiation and thermal treatments. Moreover, as a specific application, the recording of efficient NLO gratings was achieved.

Proceedings of the 6th International Workshop on Application of Lasers in Atomic Nuclei Research, LASER 2004, held in Poznan, Poland, 24-27 May, 2004 Blaszczak, Zdzislaw; Marinova, Krassimira; Markov, Boris (Eds.) 2006, ISBN: 3-540-30925-X This volume contains papers presented at the 6th International Workshop on Application of Lasers in Atomic Nuclei Research, LASER 2004, held in Poznan, Poland, 24-27 May, 2004. It should be of interest to researchers and PhD students working or interested in recent results in the nuclear structure investigation by laser spectroscopy and the new generation of experimental laser spectroscopy methods.

This thesis unifies the dissipative dynamics of an atom, particle or structure within an optical field that is influenced by the position of the atom, particle or structure itself. This allows the identification and exploration of the fundamental 'mirror-mediated' mechanisms of cavity-mediated cooling leading to the proposal of a range of new techniques based upon the same underlying principles. It also reveals powerful mechanisms for the enhancement of the radiation force cooling of micromechanical systems, using both active gain and the resonance of a cavity to which the cooled species are external. This work has implications for the cooling not only of weakly-scattering individual atoms, ions and molecules, but also for highly reflective optomechanical structures ranging from nanometre-scale cantilevers to the metre-sized mirrors of massive interferometers.

Recent state-of-the-art technologies in fabricating low-loss optical and mechanical components have significantly motivated the study of quantum-limited measurements with optomechanical devices. Such research is the main subject of this thesis. In the first part, the author considers various approaches for surpassing the standard quantum limit for force measurements. In the second part, the author proposes different experimental protocols for using optomechanical interactions to explore quantum behaviors of macroscopic mechanical objects. Even though this thesis mostly focuses on large-scale laser interferometer gravitational-wave detectors and related experiments, the general approaches apply equally well for studying small-scale optomechanical devices.

The author is the winner of the 2010 Thesis prize awarded by the Gravitational Wave International Committee.

This volume contains the proceedings of the 4th Nassau Moessbauer Symposium, held in Garden City, NY, USA in January 2006. The conference and its proceedings are dedicated to one of the pioneers of Moessbauer Spectroscopy, the late Dr. Stanley Ruby, whose original ideas, insight and enthusiasm helped create new research fields. The volume reports on the progress in various areas of applications of Moessbauer Effect.

Intended to update scientists and engineers on the current state of the art in a variety of key techniques used extensively in the fabrication of structures at the nanoscale. The present work covers the essential technologies for creating sub 25 nm features lithographically, depositing layers with nanometer control, and etching patterns and structures at the nanoscale. A distinguishing feature of this book is a focus not on extension of microelectronics fabrication, but rather on techniques applicable for building NEMS, biosensors, nanomaterials, photonic crystals, and other novel devices and structures that will revolutionize society in the coming years.

This book offers the reader a practical guide to the control and characterization of laser diode beams. Laser diodes are the most widely used lasers, accounting for 50% of the global laser market. Correct handling of laser diode beams is the key to the successful use of laser diodes, and this requires an in-depth understanding of their unique properties. Following a short introduction to the working principles of laser diodes, the book describes the basics of laser diode beams and beam propagation, including Zemax modeling of a Gaussian beam propagating through a lens. The core of the book is concerned with laser diode beam manipulations: collimating and focusing, circularization and astigmatism correction, coupling into a single mode optical fiber, diffractive optics and beam shaping, and manipulation of multi transverse mode beams. The final chapter of the book covers beam characterization methods, describing the measurement of spatial and spectral properties, including wavelength and linewidth measurement techniques. The book is a significantly revised and expanded version of the title Laser Diode Beam Basics, Manipulations and Characterizations by the same author. New topics introduced in this volume include: laser diode types and working principles, non-paraxial Gaussian beam, Zemax modeling, numerical analysis of a laser diode beam, spectral property characterization methods, and power and energy characterization techniques. The book approaches the subject in a practical way with mathematical content kept to the minimum level required, making the book a convenient reference for laser diode users.

The invention ofthe laser 25years ago resulted in powerfullight sources which led to the observation of unexpected and striking phenomena. New fields of science such as holography and nonlinear optics developed constituting the basis of this volume. The classical principle of linear superposition of light wavesdoes not hold anymore. Two laser beams crossing in a suitable material may produce a set of new beams with different directions and frequencies. The interaction of light waves can be understood by considering the optical grating structures which develop in the overlap region. The optical properties of matter become spatially modulated in the interference region of two light waves. Permanent holographic gratings have been produced in this way by photographic processes for many years. In contrast, dynamic or transient gratings disappear after the inducing light source, usually a laser, has been switched off. The grating amplitude is controlled by the light intensity. Dynamic gratings have been induced in a large number ofsolids, liquids, and gases, and are detected by diffraction, 'forced light scattering' of a third probing beam, or by self-diffraction of the light waves inducing the grating. The combined interference and diffraction effect corresponds to four-wave mixing (FWM) in the language of nonlinear optics. The process is called degenerate ifthe frequenciesofthe three incident wavesand the scattered wave are equal. Degenerate four-wave mixing (DFWM) is a simple method to achieve phase conjugation, i.e. to generate a wave which propagates time reversed with respect to an incident wave.

The optically pumped laser has made an enormous contribution to research in the part of the electromagnetic spectrum known as the far infrared, or submillimetre region. I hope that this book will be useful to both practising and prospective workers in the field, since it contains an up-to-date catalogue of measurements of the main properties of submillimetre lasers as well as an introductory review of the measurement techniques themselves. Wavelength and frequency measurements have been exhaustively compiled (in Part II of this book) along with molecule and pump identification. Part I contains a short review of the relevant measurement techniques in each of these areas and, in addition, a review of power measurements. Working in this field, as in any other, one's satisfaction is determined largely by the colleagues one has and the friends one makes along the way. I am very grateful to Dr G. Dodel, Dr L. C. Robinson and Dr G. F. Brand for introducing me to the field. Dr I. S. Falconer and Dr P. A. Krug have been good colleagues and friends. For this book in particular I am grateful to Dr Dodel, Dr K. M. Evenson, Dr H. Figger, Prof. M. Fourrier, P. Kempf, Dr K. J. Siemsen and Dr M. S. Tobin for their comments, and to Dr D. J. E. Knight for a great deal of help, including data from unpublished or obscure sources which he had gathered for his own compilation.

Femtosecond lasers opened up new avenue in materials processing due to its unique features of ultrashort pulse width and extremely high peak intensity. One of the most important features of femtosecond laser processing is that strong absorption can be induced even by materials which are transparent to the femtosecond laser beam due to nonlinear multiphoton absorption. The multiphoton absorption allows us to perform not only surface but also three-dimensionally internal microfabrication of transparent materials such as glass. This capability makes it possible to directly fabricate three-dimensional microfluidics, micromechanics, microelectronics and microoptics embedded in the glass. Further, these microcomponents can be easily integrated in a single glass microchip by the simple procedure using the femtosecond laser. Thus, the femtosecond laser processing provides some advantages over conventional methods such as traditional semiconductor processing or soft lithography for fabrication of microfluidic, optofludic and lab-on-a-chip devices and thereby many researches on this topic are currently being carried out. This book presents a comprehensive review on the state of the art and future prospects of femtosecond laser processing for fabrication of microfluidics and optofludics including principle of femtosecond laser processing, detailed fabrication procedures of each microcomponent and practical applications to biochemical analysis.