Hidden Order and Exotic Superconductivity in the Heavy-Fermion Compound URu2Si2


Book Description

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.




Handbook on the Physics and Chemistry of Rare Earths


Book Description

Handbook on the Physics and Chemistry of Rare Earths: Including Actinides, Volume 64, the latest release in this continuous series that covers all aspects of rare earth science, including chemistry, life sciences, materials science and physics, presents interesting chapters on a variety of topics, with this release including sections on Structure and properties of Ln2M3Ge5 compounds, Giant magnetocaloric effect materials, Lanthanide-based single-molecule magnets, and Magnetic Refrigeration with Lanthanide-Based Materials. - Presents up-to-date overviews and new developments in the field of rare earths, covering both their physics and chemistry - Contains individual chapters that are comprehensive and broad, along with critical reviews - Provides contributions from highly experienced, invited experts







Collective Excitations in the Antisymmetric Channel of Raman Spectroscopy


Book Description

This thesis contains three breakthrough results in condensed matter physics. Firstly, broken reflection symmetry in the hidden-order phase of the heavy-fermion material URu2Si2 is observed for the first time. This represents a significant advance in the understanding of this enigmatic material which has long intrigued the condensed matter community due to its emergent long range order exhibited at low temperatures (the so-called “hidden order”). Secondly and thirdly, a novel collective mode (the chiral spin wave) and a novel composite particle (the chiral exciton) are discovered in the three dimensional topological insulator Bi2Se3. This opens up new avenues of possibility for the use of topological insulators in photonic, optoelectronic, and spintronic devices. These discoveries are facilitated by using low-temperature polarized Raman spectroscopy as a tool for identifying optically excited collective modes in strongly correlated electron systems and three-dimensional topological insulators.




Progress in Low Temperature Physics


Book Description

A number of interrelated areas of low temperature physics are brought together in this volume. The four topics are presented as separate chapters. First is the study of the Kibble-Zurek mechanism for defect formation following quench cooling of superfluid 3He and its relation to quantum field theory. Properties of heavy fermion materials are described next with special attention to the competition between magnetism and superconductivity. Some of the newest correlated electron systems are discussed and the arguments for possible unconventional nature of the superconducting order parameter are presented for these systems, including the novel coexistence of ferromagnetism and superconductivity. Highly polarized degenerate Fermi liquids are of substantial interest in many areas of physics. The most complete description of observations of thermodynamic and transport phenomena are reviewed here for the case of polarized liquid 3He obtained by rapid melting from a polarized solid and subsequent rapid refrigeration. Properties of the melting curve of 3He, and the related technique of melting curve thermometry are described in detail.· Superfluid 3He and Quantum Field Theory· Large Scale structure of the Universe· Unconventional Superconductivity· Heavy Fermions· Quantum Phase Transitions· Polarized Fermi Liquids · Rapid Melting· 3He Melting Curve· Low Temperature Thermometry




Handbook of Superconductivity


Book Description

This is the first of three volumes of the extensively revised and updated second edition of the Handbook of Superconductivity. The past twenty years have seen rapid progress in superconducting materials, which exhibit one of the most remarkable physical states of matter ever to be discovered. Superconductivity brings quantum mechanics to the scale of the everyday world where a single, coherent quantum state may extend over a distance of metres, or even kilometres, depending on the size of a coil or length of superconducting wire. Viable applications of superconductors rely fundamentally on an understanding of this intriguing phenomena and the availability of a range of materials with bespoke properties to meet practical needs. This first volume covers the fundamentals of superconductivity and the various classes of superconducting materials, which sets the context and background for Volumes 2 and 3. Key Features: Covers the depth and breadth of the field Includes contributions from leading academics and industry professionals across the world Provides hands-on guidance to the manufacturing and processing technologies A comprehensive reference, this handbook is suitable for both graduate students and practitioners in experimental physics, materials science and multiple engineering disciplines, including electronic and electrical, chemical, mechanical, metallurgy and others.




Metals Abstracts


Book Description







Theory of Fluctuations in Superconductors


Book Description

This book presents a complete encyclopedia of superconducting fluctuations, summarising the last thirty-five years of work in the field. The first part of the book is devoted to an extended discussion of the Ginzburg-Landau phenomenology of fluctuations in its thermodynamical and time-dependent versions and its various applications. The second part deals with microscopic justification of the Ginzburg-Landau approach and presents the diagrammatic theory of fluctuations. The third part is devoted to a less-detailed review of the manifestation of fluctuations in observables: diamagnetism, magnetoconductivity, various tunneling characteristics, thermoelectricity, and NMR relaxation. The final chapters turn to the manifestation of fluctuations in unconventional superconducting systems: nanodrops, nanorings, Berezinsky-Kosterlitz-Thouless state, quantum phase transition between superconductor and insulator, and thermal and quantum fluctuations in weak superconducting systems. The book ends with a brief discussion on theories of high temperature superconductivity, where fluctuations appear as the possible protagonist of this exciting phenomenon.




The Kondo Problem to Heavy Fermions


Book Description

The behaviour of magnetic impurities in metals has posed problems to challenge the condensed matter theorist over the past 30 years. This book deals with the concepts and techniques which have been developed to meet this challenge, and with their application to the interpretation of experiments. This book will be of interest to condensed matter physicists, particularly those interested in strong correlation problems. The detailed discussions of advanced many-body techniques should make it of interest to theoretical physicists in general.