Quantum logic gates are the crucial information-processing operation of quantumcomputers. Two crucial performance metrics for logic gates are their precision andspeed. Quantum processors based on trapped ions have always been the touchstonefor gate precision, but have suffered from slow speed relative to other quantum logicplatforms such as solid state systems. This thesis shows that it is possible to acceleratethe logic "clock speed" from kHz to MHz speeds, whilst maintaining a precision of99.8%. This is almost as high as the world record for conventional trapped-ion gates,but more than 20 times faster. It also demonstrates entanglement generation in atime (480ns) shorter than the natural timescale of the ions' motion in the trap, whichstarts to probe an interesting new regime of ion trap physics. In separate experiments, some of the first "mixed-species" quantum logic gates areperformed, both between two different elements, and between different isotopes.The mixed-isotope gate is used to make the first test of the quantum-mechanical Bellinequality between two different species of isolated atoms.

This thesis presents recent developments in magnetic coupling phenomena of ferrimagnetic rare-earth transition-metal Tb-Fe alloys and coupled systems consisting of ferri-/ferromagnetic heterostructures. Taking advantage of the tunability of the exchange coupling between ferrimagnetic and ferromagnetic layers by means of stoichiometry of the Tb-Fe layer, the variable number of repetitions in the Co/Pt multilayer as well as the thickness of an interlayer spacer, it is demonstrated that large perpendicular unidirectional anisotropy can be induced at room temperature. This robust perpendicular exchange bias at room temperature opens up a path towards applications in spintronics.

This PhD thesis documents two of the highest-profile searches for supersymmetry performed at the ATLAS experiment using up to 80/fb of proton-proton collision data at a center-of-mass energy of 13 TeV delivered by the Large Hadron Collider (LHC) during its Run 2 (2015-2018). The signals of interest feature a high multiplicity of jets originating from the hadronisation of b-quarks and large missing transverse momentum, which constitutes one of the most promising final state signatures for discovery of new phenomena at the LHC. The first search is focused on the strong production of a pair of gluinos, with each gluino decaying into a neutralino and a top-antitop-quark pair or a bottom-antibottom-quark pair. The second search targets the pair production of higgsinos, with each higgsino decaying into a gravitino and a Higgs boson, which in turn is required to decay into a bottom-antibottom-quark pair. Both searches employ state-of-the-art experimental techniques and analysis strategies at the LHC, resulting in some of the most restrictive bounds available to date on the masses of the gluino,neutralino, and higgsino in the context of the models explored.

A thorough introduction to modern classical and quantum optics, appropriate for advanced undergraduates or beginning graduates. The emphasis is on building an understanding in straightforward steps. Digital cameras, LCD screens, laser welding, and the optical fibre-based internet illustrate the penetration of optics in twenty-first century life: many such modern applications are presented from first principles.
Self-contained themes covered in the book include:
- Paraxial ray optics for devices including matrix methods and aberrations.
- Interference, coherence and interferometry.
- Diffraction, spectrometry and Gaussian optics.
- Fourier optics, holography and information processing.
- Astronomical telescopes, adaptive optics and aperture synthesis.
- Maxwell's theory; scattering, absorption and dispersion in bulk materials; multilayer filters.
- Quantum phenomena, wave-particle duality and the uncertainty principle.
- Schroedinger's analysis of spectra, photon properties.
- Laser principles; He: Ne to MQW lasers and applications.
- Detectors: photodiodes, CCDs, PMs and image intensifiers; response, noise and linearity.
- Fibre optics: single mode fibre analysis; the modern data highway; fibre sensors.
- Photon-atom interactions, optical cooling and optical clocks.
- Second quantization, photon correlations, SPDC, entanglement.
This thoroughly revised and updated edition includes new coverage of photonic crystals and Bloch waves, as well as quantum dots and microcavities.

This book presents the theoretical and experimental investigations on antiferromagnetically coupled ferrimagnets and reveals new aspects of ferrimagnetic dynamics in terms of the role of angular momentum. The purpose of this book is to show readers that antiferromagnets/ferrimagnets are useful in spintronic devices in that (1) The non adiabatic spin transfer torque in antiferromagnets acts as a staggered magnetic field, which can drive the magnetic domain walls, and (2) The Gilbert damping parameter , the energy dissipation rate associated with the magnetic dynamics of ferrimagnets, is insensitive to temperature in contrast to the conventional understanding that the effective of ferrimagnets diverges at the angular momentum compensation temperature. This book provides readers with a scientific platform of ferrimagnetic dynamics, which serves as a useful basis for realizing the next generation of spintronic devices.

This book is a tribute to the scientific legacy of GianCarlo Ghirardi, who was one of the most influential scientists in the field of modern foundations of quantum theory. In this appraisal, contributions from friends, collaborators and colleagues reflect the influence of his world of thoughts on theory, experiments and philosophy, while also offering prospects for future research in the foundations of quantum physics. The themes of the contributions revolve around the physical reality of the wave function and its notorious collapse, randomness, relativity and experiments.

As an introductory account of the theory of phase transitions and critical phenomena, Elements of Phase Transitions and Critical Phenomena reflects lectures given by the authors to graduate students at their departments and is thus classroom-tested to help beginners enter the field. Most parts are written as self-contained units and every new concept or calculation is explained in detail without assuming prior knowledge of the subject. The book significantly enhances and revises a Japanese version which is a bestseller in the Japanese market and is considered a standard textbook in the field. It contains new pedagogical presentations of field theory methods, including a chapter on conformal field theory, and various modern developments hard to find in a single textbook on phase transitions. Exercises are presented as the topics develop, with solutions found at the end of the book, making the text useful for self-teaching, as well as for classroom learning.

Offers an accessible text and reference (a cosmic-ray manual) for graduate students entering the field and high-energy astrophysicists will find this an accessible cosmic-ray manual Easy to read for the general astronomer, the first part describes the standard model of cosmic rays based on our understanding of modern particle physics. Presents the acceleration scenario in some detail in supernovae explosions as well as in the passage of cosmic rays through the Galaxy. Compares experimental data in the atmosphere as well as underground are compared with theoretical models

This book highlights the overview of Spintronics, including What is Spintronics ?; Why Do We Need Spintronics ?; Comparative merit-demerit of Spintronics and Electronics ; Research Efforts put on Spintronics ; Quantum Mechanics of Spin; Dynamics of magnetic moments : Landau-Lifshitz-Gilbert Equation; Spin-Dependent Band Gap in Ferromagnetic Materials; Functionality of 'Spin' in Spintronics; Different Branches of Spintronics etc. Some important notions on basic elements of Spintronics are discussed here, such as - Spin Polarization, Spin Filter Effect, Spin Generation and Injection, Spin Accumulation, Different kinds of Spin Relaxation Phenomena, Spin Valve, Spin Extraction, Spin Hall Effect, Spin Seebeck Effect, Spin Current Measurement Mechanism, Magnetoresistance and its different kinds etc. Concept of Giant Magnetoresistance (GMR), different types of GMR, qualitative and quantitative explanation of GMR employing Resistor Network Theory are presented here. Tunnelling Magnetoresistance (TMR), Magnetic Junctions, Effect of various parameters on TMR, Measurement of spin relaxation length and time in the spacer layer are covered here. This book highlights the concept of Spin Transfer Torque (STT), STT in Ferromagnetic Layer Structures, STT driven Magnetization Dynamics, STT in Magnetic Multilayer Nanopillar etc. This book also sheds light on Magnetic Domain Wall (MDW) Motion, Ratchet Effect in MDW motion, MDW motion velocity measurements, Current-driven MDW motion, etc. The book deals with the emerging field of spintronics, i.e., Opto-spintronics. Special emphasis is given on ultrafast optical controlling of magnetic states of antiferromagnet, Spin-photon interaction, Faraday Effect, Inverse Faraday Effect and outline of different all-optical spintronic switching. One more promising branch i.e., Terahertz Spintronics is also covered. Principle of operation of spintronic terahertz emitter, choice of materials, terahertz writing of an antiferromagnetic magnetic memory device is discussed. Brief introduction of Semiconductor spintronics is presented that includes dilute magnetic semiconductor, feromagnetic semiconductor, spin polarized semiconductor devices, three terminal spintronic devices, Spin transistor, Spin-LED, and Spin-Laser. This book also emphasizes on several modern spintronics devices that includes GMR Read Head of Modern Hard Disk Drive, MRAM, Position Sensor, Biosensor, Magnetic Field sensor, Three Terminal Magnetic Memory Devices, Spin FET, Race Track Memory and Quantum Computing.

Trace and determinant functionals on operator algebras provide a means of constructing invariants in analysis, topology, differential geometry, analytic number theory, and quantum field theory. The consequent developments around such invariants have led to significant advances both in pure mathematics and theoretical physics. As the fundamental tools of trace theory have become well understood and clear general structures have emerged, so the need for specialist texts which explain the basic theoretical principles and computational techniques has become increasingly urgent. Providing a broad account of the theory of traces and determinants on algebras of differential and pseudodifferential operators over compact manifolds, this text is the first to deal with trace theory in general, encompassing a number of the principle applications and backed up by specific computations which set out in detail the nuts-and-bolts of the basic theory. Both the microanalytic approach to traces and determinants via pseudodifferential operator theory and the more computational approach directed by applications in geometric analysis, are developed in a general framework that will be of interest to mathematicians and physicists in a number of different fields.

The structure of quantum theory permits interference of indistinguishable paths. At the same time, however, it also limits such interference to certain orders and any higher-order interference is prohibited. This thesis develops and studies concepts to test quantum theory with higher-order interference using many-particle correlations, the latter being generally richer and typically more subtle than single-particle correlations. It is demonstrated that quantum theory in general allows for interference up to order 2M in M-particle correlations. Depending on the mutual coherence of the particles, however, the related interference hierarchy can terminate earlier. In this thesis, we show that mutually coherent particles can exhibit interference of the highest orders allowed. We further demonstrate that interference of mutually incoherent particles truncates already at order M+1, although interference of the latter is principally more multifaceted than their coherent counterpart. We introduce two families of many-particle Sorkin parameters, whose members are expected to be all zero when quantum mechanics holds. As proof of concept, we demonstrate the disparate vanishing of such higher-order interference terms as a function of coherence in experiments with mutually coherent and incoherent sources. Finally, we investigate the influence of exotic kinked or looped quantum paths, which are permitted by Feynman's path integral approach, in such setups.

The aim of this book is to present a statistical theory of wave scattering by complex systems -systems which have a chaotic classical dynamics, as in the case of microwave cavities and quantum dots, or possess quenched randomness, as in the case of disordered conductors- with emphasis on mesoscopic fluctuations. The universal character of the statistical behavior of these phenomena is incorporated in a natural way by approaching the problem from a Maximum-Entropy viewpoint -Shannon's information entropy is maximized, subject to the symmetries and constraints that are physically relevant- within the powerful, non-perturbative Theory of Random Matrices. This is a distinctive feature of the present book that greatly motivated our writing it. Another reason is that it collects in one place the material and notions -derived from the published work of the authors in collaboration with several co-workers, as well as from the work of others- which are scattered through research journals and textbooks on the subject. To make the book self-contained, we present in Chapters 2 and 3 the quantum theory of scattering, set in the context of quasi-one-dimensional, multichannel systems, thus related directly to scattering problems in mesoscopic physics. Chapter 4 discusses the linear-response theory of quantum electronic transport, adapted to the context of mesoscopic systems. These chapters, together with Chapter 5 on the Maximum-Entropy Approach and Chapter 8 on weak localization, have been written in a pedagogical style, and can be used as part of a graduate course. Chapters 6 and 7 discuss the problem of electronic transport through classically chaotic cavities and quasi-one-dimensional disordered systems. There are many exercises, most of them worked out in detail, distributed throughout the book. This should help graduate students, their teachers and the research scholars interested generally in the subject of quantum transport through disordered and chaotic systems in their preparation for it, and beyond.

The last decade witnessed an increasing interest of mathematicians in prob lems originated in mathematical physics. As a result of this effort, the scope of traditional mathematical physics changed considerably. New problems es pecially those connected with quantum physics make use of new ideas and methods. Together with classical and functional analysis, methods from dif ferential geometry and Lie algebras, the theory of group representation, and even topology and algebraic geometry became efficient tools of mathematical physics. On the other hand, the problems tackled in mathematical physics helped to formulate new, purely mathematical, theorems. This important development must obviously influence the contemporary mathematical literature, especially the review articles and monographs. A considerable number of books and articles appeared, reflecting to some extend this trend. In our view, however, an adequate language and appropriate methodology has not been developed yet. Nowadays, the current literature includes either mathematical monographs occasionally using physical terms, or books on theoretical physics focused on the mathematical apparatus. We hold the opinion that the traditional mathematical language of lem mas and theorems is not appropriate for the contemporary writing on mathe matical physics. In such literature, in contrast to the standard approaches of theoretical physics, the mathematical ideology must be utmost emphasized and the reference to physical ideas must be supported by appropriate mathe matical statements. Of special importance are the results and methods that have been developed in this way for the first time."

This thesis presents a revolutionary technique for modelling the dynamics of a quantum system that is strongly coupled to its immediate environment. This is a challenging but timely problem. In particular it is relevant for modelling decoherence in devices such as quantum information processors, and how quantum information moves between spatially separated parts of a quantum system. The key feature of this work is a novel way to represent the dynamics of general open quantum systems as tensor networks, a result which has connections with the Feynman operator calculus and process tensor approaches to quantum mechanics. The tensor network methodology developed here has proven to be extremely powerful: For many situations it may be the most efficient way of calculating open quantum dynamics. This work is abounds with new ideas and invention, and is likely to have a very significant impact on future generations of physicists.

The second edition of this successful textbook provides an up-to-date account of the optical physics of solid state materials. The basic principles of absorption, reflection, luminescence, and light scattering are covered for a wide range of materials, including insulators, semiconductors and metals. The text starts with a review of classical optics, and then moves on to the treatment of optical transition rates by quantum theory. In addition to the traditional discussion of crystalline materials, glasses and molecular solids are also covered.
The first edition included a number of subjects that are not normally covered in standard texts, notably semiconductor quantum wells, molecular materials, vibronic solid state lasers, and nonlinear optics. The basic structure of the second edition is unchanged, but all of the chapters have been updated and improved. Futhermore, a number of important new topics have been added, including:
DT Optical control of spin
DT Quantum dots
DT Plasmonics
DT Negative refraction
DT Carbon nanostructures (graphene, nanotubes and fullerenes)
DT NV centres in diamond
The text is aimed at final year undergraduates, masters students and researchers. It is mainly written for physicists, but might also be useful for electrical engineers, materials scientists and physical chemists. The topics are written in a clear tutorial style with worked examples, chapter summaries and exercises.
To request a copy of the Solutions Manual, visit: http: //global.oup.com/uk/academic/physics/admin/solutions

This research monograph offers an introduction to advanced quantum field theoretical techniques for many-particle systems beyond perturbation theory. Several schemes for resummation of the Feynman diagrams are described. The resulting approximations are especially well suited for strongly correlated fermion and boson systems. Also considered is the crossover from BCS superconductivity to Bose--Einstein condensation in fermion systems with strong attractive interaction. In particular, a field theoretic formulation of "bosonization" is presented; it is published here for the first time. This method is applied to the fractional quantum Hall effect, to the Coulomb plasma, and to several exactly solvable models.

There is a continuing growth of interest in the computer simulation of materials at the atomic scale, using a variety of academic and commercial computer programs. In all such programs there is some physical model of the inter-atomic forces, which may be based on something as simple as a pair interaction, such as the Lennard-Jones model, or as complex as a self-consistent, all-electron solution of the quantum mechanical problem. For a student or researcher, the basis of such models is often shrouded in mystery. It is usually unclear how well founded they are, since it is hard to find a discussion of the physical assumptions that have been made in their construction. The lack of clear understanding of the scope and limitations of a given model may lead to its innocent misuse, resulting either in unfair criticism of the model or in the dissemination of nonsensical results.
In the present book, models of inter-atomic forces are derived from a common physical basis, namely the density functional theory. The interested reader will be able to follow the detailed derivation of pairwise potentials in simple metals, tight-binding models from the simplest to the most sophisticated (self-consistent) kind, and various ionic models. The book is self-contained, requiring no more background than provided by an undergraduate quantum mechanics course. It aims to furnish the reader with a critical appreciation of the broad range of models in current use, and to provide the tools for understanding other variants that are described in the literature. Some of the material is new, and some pointers are given to possible future avenues of model development.

Astrophysical observations implying the existence of Dark Matter and Dark Energy, which are not described by the Standard Model (SM) of particle physics, have led to extensions of the SM predicting new particles that could be directly produced at the Large Hadron Collider (LHC) at CERN. Based on 2015 and 2016 ATLAS proton-proton collision data, this thesis presents searches for the supersymmetric partner of the top quark, for Dark Matter, and for DarkEnergy, in signatures with jets and missing transverse energy. Muon detection is key to some of the most important LHC physics results, including the discovery of the Higgs boson and the measurement of its properties. The efficiency with which muons can be detected with the ATLAS detector is measured using Z boson decays. The performance of high-precision Monitored Drift Tube muon chambers under background rates similar to the ones expected for the High Luminosity-LHC is studied.

Peter Byrne tells the story of Hugh Everett III (1930-1982), whose "many worlds" theory of multiple universes has had a profound impact on physics and philosophy. Using Everett's unpublished papers (recently discovered in his son's basement) and dozens of interviews with his friends, colleagues, and surviving family members, Byrne paints, for the general reader, a detailed portrait of the genius who invented an astonishing way of describing our complex universe from the inside. Everett's mathematical model (called the "universal wave function") treats all possible events as "equally real," and concludes that countless copies of every person and thing exist in all possible configurations spread over an infinity of universes: many worlds.
Afflicted by depression and addictions, Everett strove to bring rational order to the professional realms in which he played historically significant roles. In addition to his famous interpretation of quantum mechanics, Everett wrote a classic paper in game theory; created computer algorithms that revolutionized military operations research; and performed pioneering work in artificial intelligence for top secret government projects. He wrote the original software for targeting cities in a nuclear hot war; and he was one of the first scientists to recognize the danger of nuclear winter. As a Cold Warrior, he designed logical systems that modeled "rational" human and machine behaviors, and yet he was largely oblivious to the emotional damage his irrational personal behavior inflicted upon his family, lovers, and business partners.
He died young, but left behind a fascinating record of his life, including correspondence with such philosophically inclined physicists as Niels Bohr, Norbert Wiener, and John Wheeler. These remarkable letters illuminate the long and often bitter struggle to explain the paradox of measurement at the heart of quantum physics. In recent years, Everett's solution to this mysterious problem-the existence of a universe of universes-has gained considerable traction in scientific circles, not as science fiction, but as an explanation of physical reality.

This thesis reports the calculation of neutrino production for the T2K experiment; the most precise a priori estimate of neutrino production that has been achieved for any accelerator-based neutrino oscillation experiment to date. The production of intense neutrino beams at accelerator facilities requires exceptional understanding of chains of particle interactions initiated within extended targets. In this thesis, the calculation of neutrino production for T2K has been improved by using measurements of particle production from a T2K replica target, taken by the NA61/SHINE experiment. This enabled the reduction of the neutrino production uncertainty to the level of 5%, which will have a significant impact on neutrino oscillation and interaction measurements by T2K in the coming years. In addition to presenting the revised flux calculation methodology in an accessible format, this thesis also reports a joint T2K measurement of muon neutrino and antineutrino disappearance, and the accompanying electron neutrino and antineutrino appearance, with the updated beam constraint.

Theoretical investigations of atoms and molecules interacting with pulsed or continuous wave lasers up to atomic field strengths on the order of 10 DEGREES16 W/cm are leading to an understanding of many challenging experimental discoveries. This book deals with the basics of femtosecond physics and goes up to the latest applications of new phenomena. The book presents an introduction to laser physics with mode-locking and pulsed laser operation. The solution of the time-dependent Schrodinger equation is discussed both analytically and numerically. The basis for the non-perturbative treatment of laser-matter interaction in the book is the numerical solution of the time-dependent Schrodinger equation. The light field is treated classically, and different possible gauges are discussed. Physical phenomena, ranging from Rabi-oscillations in two-level systems to the ionization of atoms, the generation of high harmonics, the ionization and dissociation of molecules as well as the control of chemical reactions are presented and discussed on a fundamental level. In this way the theoretical background for state of the art experiments with strong and short laser pulses is given. The text is augmented by more than thirty exercises, whose worked-out solutions are given in the last chapter. Some detailed calculations are performed in the appendices. Furthermore, each chapter ends with references to more specialized literature."

First published in 1983, this book has become a classic among advanced textbooks. The new fourth edition maintains the high standard of its predecessors. The book offers basic knowledge of field theory and particle phenomenology. The author presents the basic facts of quark and gluon physics in pedagogical form. Explanations of theory are supported throughout with experimental findings. The text provides readers with sufficient understanding to follow modern research articles. This fourth edition presents a new section on heavy quark effective theories, more material on lattice QCD and on chiral perturbation theory.

Volume 1 of this three-part series introduces the fundamental concepts of quantum field theory using the formalism of canonical quantization. This volume is intended for use as a text for an introductory quantum field theory course that can include both particle and condensed matter physics students. Dr. Strickland starts with a brief review of classical field theory and uses this as a jumping off point for the quantization of classical field, thereby promoting them to proper quantum fields. He then presents the formalism for real and complex scalar field theories, fermion field quantization, gauge field quantization, toy models of the nuclear interaction, and finally the full Lagrangian for QED and its renormalization. Part of IOP Series in Nuclear Medicine.

The relation between quantum theory and the theory of gravitation remains one of the most outstanding unresolved issues of modern physics. According to general expectation, general relativity as well as quantum (field) theory in a fixed background spacetime cannot be fundamentally correct. Hence there should exist a broader theory comprising both in appropriate limits, i.e., quantum gravity. This book gives readers a comprehensive introduction accessible to interested non-experts to the main issues surrounding the search for quantum gravity. These issues relate to fundamental questions concerning the various formalisms of quantization; specific questions concerning concrete processes, like gravitational collapse or black-hole evaporation; and the all important question concerning the possibility of experimental tests of quantum-gravity effects.

This biography of the famous Soviet physicist Leonid Isaakovich Mandelstam (1889-1944), who became a Professor at Moscow State University in 1925 and an Academician (the highest scientific title in the USSR) in 1929, describes his contributions to both physics and technology. It also discusses the scientific community that formed around him, commonly known as the Mandelstam School. By doing so, it places Mandelstam's life story in its cultural context: the context of German University (until 1914), the First World War, the Civil War, and the development of the Socialist Revolution (until 1925) and the young socialist country. The book considers various general issues, such as the impact of German scientific culture on Russian science; the problems and fates of Russian intellectuals during the revolutionary and post-revolutionary years; the formation of the Soviet Academy of Science, the State Academy; and the transformation of the system of higher education in the USSR during the 1920s and 1930s. Further, it reconstructs Mandelstam's philosophy of science and his approach to the social and ethical function of science and science education based on his fundamental writings and lecture notes. This reconstruction is enhanced by extensive use of previously unpublished archive material as well as the transcripts of personal interviews conducted by the author. The book also discusses the biographies of Mandelstam's friends and collaborators: German mathematician and philosopher Richard von Mises, Soviet Communist Party official and philosopher B.M.Hessen, Russian specialist in radio engineering N.D.Papalexy, the specialists in non-linear dynamics A.A.Andronov, S.E. Chaikin, A.A.Vitt and the plasma physicist M.A.Leontovich. This second, extended edition reconstructs the social and economic backgrounds of Mandelstam and his colleagues, describing their positions at the universities and the institutes belonging to the Academy of Science. Additionally, Mandelstam's philosophy of science is investigated in connection with the ideological attacks that occurred after Mandelstam's death, particularly the great mathematician A.D.Alexandrov's criticism of Mandelstam's operationalism.