Metamaterials, artificial electromagnetic media achieved by structuring on the subwave-length-scale were initially suggested for the negative index and superlensing. They became a paradigm for engineering electromagnetic space and controlling propagation of waves. The research agenda is now shifting on achieving tuneable, switchable, nonlinear and sensing functionalities. The time has come to talk about the emerging research field of metadevices employing active and tunable metamaterials with unique functionalities achieved by structuring of functional matter on the subwave-length scale. This book presents the first systematic and comprehensive summary of the reviews written by the pioneers and top-class experts in the field of metamaterials. It addresses many grand challenges of the cutting edge research for creating smaller and more efficient photonic structures and devices.

This critical volume examines the different methods used for the synthesis of a great number of photocatalysts, including TiO2, ZnO and other modified semiconductors, as well as characterization techniques used for determining the optical, structural and morphological properties of the semiconducting materials. Additionally, the authors discuss photoelectrochemical methods for determining the light activity of the photocatalytic semiconductors by means of measurement of properties such as band gap energy, flat band potential and kinetics of hole and electron transfer. Photocatalytic Semiconductors: Synthesis, Characterization and Environmental Applications provide an overview of the semiconductor materials from first- to third-generation photocatalysts and their applications in wastewater treatment and water disinfection. The book further presents economic and toxicological aspects in the production and application of photocatalytic materials.

In this thesis, the author has developed a high-resolution spin-resolved photoemission spectrometer that achieves the world-best energy resolution of 8 meV. The author has designed a new, highly efficient mini Mott detector that has a large electron acceptance angle and an atomically flat gold target to enhance the efficiency of detecting scattered electrons. The author measured the electron and spin structure of Bi thin film grown on a Si(111) surface to study the Rashba effect. Unlike the conventional Rashba splitting, an asymmetric in-plane spin polarization and a tremendous out-of-plane spin component were observed. Moreover, the author found that the spin polarization of Rashba surface states is reduced by decreasing the film thickness, which indicates the considerable interaction of Rashba spin-split states between the surface and Bi/Si interface.

This thesis addresses the intriguing topic of the quantum tunnelling of many-body systems such as Bose-Einstein condensates. Despite the enormous amount of work on the tunneling of a single particle through a barrier, we know very little about how a system made of several or of many particles tunnels through a barrier to open space. The present work uses numerically exact solutions of the time-dependent many-boson Schrödinger equation to explore the rich physics of the tunneling to open space process in ultracold bosonic particles that are initially prepared as a Bose-Einstein condensate and subsequently allowed to tunnel through a barrier to open space. The many-body process is built up from concurrently occurring single particle processes that are characterized by different momenta. These momenta correspond to the chemical potentials of systems with decreasing particle number. The many-boson process exhibits exciting collective phenomena: the escaping particles fragment and lose their coherence with the source and among each other, whilst correlations build up within the system. The detailed understanding of the many-body process is used to devise and test a scheme to control the final state, momentum distributions and even the correlation dynamics of the tunneling process.

This work studies the magnetic behavior of ZnO nanoparticles capped with different organic molecules and showing room-temperature ferromagnetism (RTFM). Of particular significance is the combination of element-specific X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) techniques, which demonstrates the intrinsic occurrence of RTFM in these systems and indicates that it is not related to the 3-D states of the metallic cation but is relayed along the conduction band of the semiconductor. The discovery of room-temperature ferromagnetism (RTFM) in semiconductors holds great promise in future spintronics technologies.   Further results presented here include O K-edge XMCD studies, which demonstrate that the oxygen ions have a ferromagnetic response in these ZnO-based systems, providing the first direct support for claims regarding the appearance of oxygen ferromagnetism in oxide semiconductors at the nanoscale.

Epitaxial integration of III-V semiconductors on silicon substrates has been desired over decades for high application potential in microelectronics, photovoltaics, and beyond. The performance of optoelectronic devices is still severely impaired by critical defect mechanisms driven by the crucial polar-on-nonpolar heterointerface. This thesis reports almost lattice-matched growth of thin gallium phosphide films as a viable model system for III-V/Si(100) interface investigations. The impact of antiphase disorder on the heteroepitaxial growth surface provides quantitative optical in situ access to one of the most notorious defect mechanisms, even in the vapor phase ambient common for compound semiconductor technology. Precise control over the surface structure of the Si(100) substrates prior to III-V nucleation prevents the formation of antiphase domains. The hydrogen-based process ambient enables the preparation of anomalous double-layer step structures on Si(100), highly beneficial for subsequent III-V integration.

This book reviews a range of quantum phenomena in novel nanoscale transistors called FinFETs, including quantized conductance of 1D transport, single electron effect, tunneling transport, etc. The goal is to create a fundamental bridge between quantum FinFET and nanotechnology to stimulate readers' interest in developing new types of semiconductor technology. Although the rapid development of micro-nano fabrication is driving the MOSFET downscaling trend that is evolving from planar channel to nonplanar FinFET, silicon-based CMOS technology is expected to face fundamental limits in the near future. Therefore, new types of nanoscale devices are being investigated aggressively to take advantage of the quantum effect in carrier transport. The quantum confinement effect of FinFET at room temperatures was reported following the breakthrough to sub-10nm scale technology in silicon nanowires. With chapters written by leading scientists throughout the world, Toward Quantum FinFET provides a comprehensive introduction to the field as well as a platform for knowledge sharing and dissemination of the latest advances. As a roadmap to guide further research in an area of increasing importance for the future development of materials science, nanofabrication technology, and nano-electronic devices, the book can be recommended for Physics, Electrical Engineering, and Materials Science departments, and as a reference on micro-nano electronic science and device design. Offers comprehensive coverage of novel nanoscale transistors with quantum confinement effect Provides the keys to understanding the emerging area of the quantum FinFET Written by leading experts in each research area Describes a key enabling technology for research and development of nanofabrication and nanoelectronic devices

In this thesis, the author investigates hidden-order phase transition at T0 = 17.5 K in the heavy-fermion URu2Si2. The four-fold rotational symmetry breaking in the hidden order phase, which imposes a strong constraint on the theoretical model, is observed through the magnetic torque measurement. The translationally invariant phase with broken rotational symmetry is interpreted as meaning that the hidden-order phase is an electronic "nematic" phase. The observation of such nematicity in URu2Si2 indicates a ubiquitous nature among the strongly correlated electron systems. The author also studies the superconducting state of URu2Si2 below Tc = 1.4 K, which coexists with the hidden-order phase. A peculiar vortex penetration in the superconducting state is found, which may be related to the rotational symmetry breaking in the hidden-order phase. The author also identifies a vortex lattice melting transition. This transport study provides essential clues to the underlying issue of quasiparticle dynamics as to whether a quasiparticle Bloch state is realized in the periodic vortex lattice.

Recent developments in the technology of silicon nanocrystals and silicon nanostructures, where quantum-size effects are important, are systematically described including examples of device applications. Due to the strong quantum confinement effect, the material properties are freed from the usual indirect- or direct-bandgap regime, and the optical, electrical, thermal, and chemical properties of these nanocrystalline and nanostructured semiconductors are drastically changed from those of bulk silicon. In addition to efficient visible luminescence, various other useful material functions are induced in nanocrystalline silicon and periodic silicon nanostructures. Some novel devices and applications, in fields such as photonics (electroluminescence diode, microcavity, and waveguide), electronics (single-electron device, spin transistor, nonvolatile memory, and ballistic electron emitter), acoustics, and biology, have been developed by the use of these quantum-induced functions in ways different from the conventional scaling principle for ULSI.

The thermal processing of materials ranges from few fem to seconds by Swift Heavy Ion Implantation to about one second using advanced Rapid Thermal Annealing. This book offers after an historical excursus selected contributions on fundamental and applied aspects of thermal processing of classical elemental semiconductors and other advanced materials including nanostructures with novel optoelectronic, magnetic, and superconducting properties. Special emphasis is given on the diffusion and segregation of impurity atoms during thermal treatment. A broad range of examples describes the solid phase and/or liquid phase processing of elemental and compound semiconductors, dielectric composites and organic materials.

Semiconductor heterostructures represent the backbone for an increasing variety of electronic and photonic devices, for applications including information storage, communication and material treatment, to name but a few. Novel structural and material concepts are needed in order to further push the performance limits of present devices and to open up new application areas. This thesis demonstrates how key performance characteristics of three completely different types of semiconductor lasers can be tailored using clever nanostructure design and epitaxial growth techniques. All aspects of laser fabrication are discussed, from design and growth of nanostructures using metal-organic vapor-phase epitaxy, to fabrication and characterization of complete devices.

This book presents an overview of material-specific factors that influence Tc and give rise to diverse Tc values for copper oxides and iron-based high- Tc superconductors on the basis of more than 25 years of experimental data, to most of which the author has made important contributions. The book then explains why both compounds are distinct from others with similar crystal structure and whether or not one can enhance Tc, which in turn gives a hint on the unresolved pairing mechanism. This is an unprecedented new approach to the problem of high-temperature superconductivity and thus will be inspiring to both specialists and non-specialists interested in this field. Readers will receive in-depth information on the past, present, and future of high-temperature superconductors, along with special, updated information on what the real highest Tc values are and particularly on the possibility of enhancing Tc for each member material, which is important for application. At this time, the highest Tc has not been improved for 20 years, and no new superconductors have been discovered for 5 years. This book will encourage researchers as well as graduate-course students not to give up on the challenges in the future of high- Tc superconductivity.

This book provides a unified and complete theory for semiconductor lasers, covering topics ranging from the principles of classical and quantum mechanics to highly advanced levels for readers who need to analyze the complicated operating characteristics generated in the real application of semiconductor lasers. The author conducts a theoretical analysis especially on the instabilities involved in the operation of semiconductor lasers. A density matrix into the theory for semiconductor lasers is introduced and the formulation of an improved rate equation to help understand the mode competition phenomena which cause the optical external feedback noise is thoroughly described from the basic quantum mechanics. The derivation of the improved rate equation will allow readers to extend the analysis for the different types of semiconductor materials and laser structures they deal with. This book is intended not only for students and academic researchers but also for engineers who develop lasers for the market, as the advanced topics covered are dedicated to real problems in implementing semiconductor lasers for practical use.

This thesis breaks new ground in the physics of photonic circuits for quantum optical applications. The photonic circuits are based either on ridge waveguides or photonic crystals, with embedded quantum dots providing the single qubit, quantum optical emitters. The highlight of the thesis is the first demonstration of a spin-photon interface using an all-waveguide geometry, a vital component of a quantum optical circuit, based on deterministic single photon emission from a single quantum dot. The work makes a further important contribution to the field by demonstrating the effects and limitations that inevitable disorder places on photon propagation in photonic crystal waveguides, a further key component of quantum optical circuits. Overall the thesis offers a number of highly novel contributions to the field; those on chip circuits may prove to be the only means of scaling up the highly promising quantum-dot-based quantum information technology.

This monograph solely investigates the Debye Screening Length (DSL) in semiconductors and their nano-structures. The materials considered are quantized structures of non-linear optical, III-V, II-VI, Ge, Te, Platinum Antimonide, stressed materials, Bismuth, GaP, Gallium Antimonide, II-V and Bismuth Telluride respectively. The DSL in opto-electronic materials and their quantum confined counterparts is studied in the presence of strong light waves and intense electric fields on the basis of newly formulated electron dispersion laws that control the studies of such quantum effect devices. The suggestions for the experimental determination of 2D and 3D DSL and the importance of measurement of band gap in optoelectronic materials under intense built-in electric field in nano devices and strong external photo excitation (for measuring photon induced physical properties) have also been discussed in this context. The influence of crossed electric and quantizing magnetic fields on the DSL and the DSL in heavily doped semiconductors and their nanostructures has been investigated. This monograph contains 150 open research problems which form the integral part of the text and are useful for both PhD students and researchers in the fields of solid-state sciences, materials science, nano-science and technology and allied fields in addition to the graduate courses in modern semiconductor nanostructures.

This book provides the analytical theory of complex systems composed of a large number of high-Q dielectric resonators. Spherical and cylindrical dielectric resonators with inferior and also whispering gallery oscillations allocated in various lattices are considered. A new approach to S-matrix parameter calculations based on perturbation theory of Maxwell equations, developed for a number of high-Q dielectric bodies, is introduced. All physical relationships are obtained in analytical form and are suitable for further computations. Essential attention is given to a new unified formalism of the description of scattering processes. The general scattering task for coupled eigen oscillations of the whole system of dielectric resonators is described. The equations for the expansion coefficients are explained in an applicable way. The temporal Green functions for the dielectric resonator are presented. The scattering process of short pulses in dielectric filter structures, dielectric antennas and lattices of dielectric resonators is discussed.

Topological Insulators (TIs) are insulators in the bulk, but have exotic metallic states at their surfaces. The topology, associated with the electronic wavefunctions of these systems, changes when passing from the bulk to the surface. This work studies, by means of infrared spectroscopy, the low energy optical conductivity of Bismuth based TIs in order to identify the extrinsic charge contribution of the bulk and to separate it from the intrinsic contribution of the surface state carriers. The extensive results presented in this thesis definitely shows the 2D character of the carriers in Bismuth-based topological insulators. The experimental apparatus and the FTIR technique, the theory of optical properties and Surface Plasmon Polaritons, as well as sample preparation of both crystals and thin films, and the analysis procedures are thoroughly described.

The minimum temperature in the natural universe is 2.7 K. Laboratory refrigerators can reach temperatures in the microkelvin range. Modern industrial refrigerators cool foods at 200 K, whereas space mission payloads must be capable of working at temperatures as low as 20 K. Superconducting magnets used for NMR work at 4.2 K. Hence the properties of materials must be accurately known also at cryogenic temperatures. This book provides a guide for engineers, physicists, chemists, technicians who wish to approach the field of low-temperature material properties. The focus is on the thermal properties and a large spectrum of experimental cases is reported. The book presents updated tables of low-temperature data on materials and a thorough bibliography supplements any further research. Key Features include: Degrees Detailed technical description of experiments Degrees Description of the newest cryogenic apparatus Degrees Offers data on cryogenic properties of the latest new materials Degrees Current reference review

This thesis focuses on two areas - the development of miniature plastic lasers that can be powered by LEDs, and the application of these lasers as highly sensitive sensors for vapours of nitroaromatic explosives (e.g. TNT). Polymer lasers are extremely compact visible lasers; the research described in the thesis is groundbreaking, driving forward the technology and physical understanding to allow these lasers to be routinely pumped by a single high-power LED. A notable advance in the work is the demonstration of nanoimprinted polymer lasers, which exhibit the world's lowest pump threshold densities by two orders of magnitude. The thesis also advances the application of these compact, novel lasers as highly sensitive detectors of explosive vapours, demonstrating that rapid detection can be achieved when microporous polymers are used. This work also demonstrates a prototype CMOS-based microsystem sensor for explosive vapours, exploiting a new detection approach.

Neutron stars are the most compact astronomical objects in the universe which are accessible by direct observation. Studying neutron stars means studying physics in regimes unattainable in any terrestrial laboratory. Understanding their observed complex phenomena requires a wide range of scientific disciplines, including the nuclear and condensed matter physics of very dense matter in neutron star interiors, plasma physics and quantum electrodynamics of magnetospheres, and the relativistic magneto-hydrodynamics of electron-positron pulsar winds interacting with some ambient medium. Not to mention the test bed neutron stars provide for general relativity theories, and their importance as potential sources of gravitational waves. It is this variety of disciplines which, among others, makes neutron star research so fascinating, not only for those who have been working in the field for many years but also for students and young scientists. The aim of this book is to serve as a reference work which not only reviews the progress made since the early days of pulsar astronomy, but especially focuses on questions such as: "What have we learned about the subject and how did we learn it?", "What are the most important open questions in this area?" and "What new tools, telescopes, observations, and calculations are needed to answer these questions?". All authors who have contributed to this book have devoted a significant part of their scientific careers to exploring the nature of neutron stars and understanding pulsars. Everyone has paid special attention to writing educational comprehensive review articles with the needs of beginners, students and young scientists as potential readers in mind. This book will be a valuable source of information for these groups.

This book provides a state of the art report of the knowledge accumulated in graphene research. The fascination with graphene has been growing very rapidly in recent years and the physics of graphene is now becoming one of the most interesting as well as the most fast-moving topics in condensed-matter physics. The Nobel prize in physics awarded in 2010 has given a tremendous impetus to this topic. The horizon of the physics of graphene is ever becoming wider, where physical concepts go hand in hand with advances in experimental techniques. Thus this book is expanding the interests to not only transport but optical and other properties for systems that include multilayer as well as monolayer graphene systems. The book comprises experimental and theoretical knowledge. The book is also accessible to graduate students.

This thesis combines highly accurate optical spectroscopy data on the recently discovered iron-based high-temperature superconductors with an incisive theoretical analysis. Three outstanding results are reported: (1) The superconductivity-induced modification of the far-infrared conductivity of an iron arsenide with minimal chemical disorder is quantitatively described by means of a strong-coupling theory for spin fluctuation mediated Cooper pairing. The formalism developed in this thesis also describes prior spectroscopic data on more disordered compounds. (2) The same materials exhibit a sharp superconductivity-induced anomaly for photon energies around 2.5 eV, two orders of magnitude larger than the superconducting energy gap. The author provides a qualitative interpretation of this unprecedented observation, which is based on the multiband nature of the superconducting state. (3) The thesis also develops a comprehensive description of a superconducting, yet optically transparent iron chalcogenide compound. The author shows that this highly unusual behavior can be explained as a result of the nanoscopic coexistence of insulating and superconducting phases, and he uses a combination of two complementary experimental methods - scanning near-field optical microscopy and low-energy muon spin rotation - to directly image the phase coexistence and quantitatively determine the phase composition. These data have important implications for the interpretation of data from other experimental probes.

Quantum dots as nanomaterials have been extensively investigated in the past several decades from growth to characterization to applications. As the basis of future developments in the field, this book collects a series of state-of-the-art chapters on the current status of quantum dot devices and how these devices take advantage of quantum features. Written by 56 leading experts from 14 countries, the chapters cover numerous quantum dot applications, including lasers, LEDs, detectors, amplifiers, switches, transistors, and solar cells. Quantum Dot Devices is appropriate for researchers of all levels of experience with an interest in epitaxial and/or colloidal quantum dots. It provides the beginner with the necessary overview of this exciting field and those more experienced with a comprehensive reference source.

Semiconductor nanostructures such as nanowires are promising building blocks of future nanoelectronic, nanophotonic and nanosensing devices. Their physical properties are primarily determined by the epitaxy process which is rather different from the conventional thin film growth. This book shows how the advanced nucleation theory can be used in modeling of growth properties, morphology and crystal phase of such nanostructures. The book represents a systematic account of modern nucleation theory in open systems, nanostructure nucleation and growth mechanisms, and possibilities for tuning the nanostructure properties to the desired values.

Advances in the synthesis of new materials with often complex, nano-scaled structures require increasingly sophisticated experimental techniques that can probe the electronic states, the atomic magnetic moments and the magnetic microstructures responsible for the properties of these materials. At the same time, progress in synchrotron radiation techniques has ensured that these light sources remain a key tool of investigation, e.g. synchrotron radiation sources of the third generation are able to support magnetic imaging on a sub-micrometer scale. With the Sixth Mittelwihr School on Magnetism and Synchrotron Radiation the tradition of teaching the state-of-the-art on modern research developments continues and is expressed through the present set of extensive lectures provided in this volume. While primarily aimed at postgraduate students and newcomers to the field, this volume will also benefit researchers and lecturers actively working in the field.