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Written by a leading expert on the electromagnetic design and engineering of superconducting accelerator magnets, this book offers the most comprehensive treatment of the subject to date. In concise and easy-to-read style, the author lays out both the mathematical basis for analytical and numerical field computation and their application to magnet design and manufacture. Of special interest is the presentation of a software-based design process that has been applied to the entire production cycle of accelerator magnets from the concept phase to field optimization, production follow-up, and hardware commissioning. Included topics: Technological challenges for the Large Hadron Collider at CERN Algebraic structures and vector fields Classical vector analysis Foundations of analytical field computation Fields and Potentials of line currents Harmonic fields The conceptual design of iron- and coil-dominated magnets Solenoids Complex analysis methods for magnet design Elementary beam optics and magnet polarities Numerical field calculation using finite- and boundary-elements Mesh generation Time transient effects in superconducting magnets, including superconductor magnetization and cable eddy-currents Quench simulation and magnet protection Mathematical optimization techniques using genetic and deterministic algorithms Practical experience from the electromagnetic design of the LHC magnets illustrates the analytical and numerical concepts, emphasizing the relevance of the presented methods to a great many applications in electrical engineering. The result is an indispensable guide for high-energy physicists, electrical engineers, materials scientists, applied mathematicians, and systems engineers.

Presenting in a coherent and accessible fashion current results in nanomagnetism, this book constitutes a comprehensive, rigorous and readable account, from first principles of the classical and quantum theories underlying the dynamics of magnetic nanoparticles subject to thermal fluctuations.
Starting with the Larmor-like equation for a giant spin, both the stochastic (Langevin) equation of motion of the magnetization and the associated evolution (Fokker–Planck) equation for the distribution function of the magnetization orientations of ferromagnetic nanoparticles (classical spins) in a heat bath are developed along with their solution (using angular momentum theory) for arbitrary magnetocrystalline-Zeeman energy. Thus, observables such as the magnetization reversal time, relaxation functions, dynamic susceptibilities, etc. are calculated and compared with the predictions of classical escape rate theory including in the most general case spin-torque-transfer. Regarding quantum effects, which are based on the reduced spin density matrix evolution equation in Hilbert space as is described at length, they are comprehensively treated via the Wigner–Stratonovich formulation of the quantum mechanics of spins via their orientational quasi-probability distributions on a classically meaningful representation space. Here, as suggested by the relevant Weyl symbols, the latter is the configuration space of the polar angles. Hence, one is led, by mapping the reduced density matrix equation onto that space, to a master equation for the quasi-probability evolution akin to the Fokker–Planck equation which may be solved in a similar way. Thus, one may study in a classical-like manner the evolution of observables with spin number ranging from an elementary spin to molecular clusters to the classical limit, viz. a nanoparticle. The entire discussion hinges on the one-to-one correspondence between polarization operators in Hilbert space and the spherical harmonics allied to concepts of spin coherent states long familiar in quantum optics.
Catering for the reader with only a passing knowledge of statistical and quantum mechanics, the book serves as an introductory text on a complicated subject where the literature is remarkably sparse.