High Temperature Superconductivity

D.P Tunstall, D.W Barford

• Publisher: CRC Press
• Year: 2021
• Print ISBN: 9780367836184
• eBook ISBN: 9781000447996
• Topic: Mathematics
• Subtopic: Mathematics General
• Index: Mathematics

High Temperature Superconductivity provides a broad survey of high temperature superconductivity, discussing the adaptations of experimental and theoretical techniques and methods that take advantage of the revolutionary properties of high temperature superconductors. Distinguished engineers, chemists, and experimental and theoretical physicists introduce their own particular area of the field before going on to explain current theories and techniques. The book is divided into three sections: materials, mechanisms, and devices. Topics covered include synthetic approaches to the growth of new materials; optical, magnetic, and electrical characterization of synthesized materials; strong correlations; the magnon pairing mechanism; and technical background of device performance in new materials. A coherent introduction to high temperature superconductivity, this volume will be invaluable to researchers in condensed matter physics, chemistry, materials science, and engineering.

Introduction to the Theory of Strongly Correlated Electrons

Τ Μ Rice
ETH-Hönggerburg Zürich

1 Introduction

The high-T_c superconductors continue to pose the most pressing problem in solid state theory. A lot has been learned but in many cases this knowledge has only deepened the mystery. The goal is clear - to find and to solve the simplest model that can describe the key features of the generic phase diagram of the cuprates. These are the rapid suppression of the antiferromagnetic order with doping leading to an anomalous normal state, with unusual transport, optical and magnetic properties that have been reviewed in the contributions of Thomas, Alloul and Sawatzky in this volume, and leading also to superconductivity with a substantially higher energy scale than in any other material.

Further the experimental evidence points to a continuous and smooth evolution with doping away from a Mott insulating behaviour which occurs for the stoichiometric compositions with formal valence Cu²⁺. As the simplest example, consider the crystal structure itself. This is after all determined by the chemical bonding pattern and since it changes only slightly with doping, a radical change in the electronic structure is ruled out. Other experiments which offer direct evidence in favour of this hypothesis are, for example, nmr investigations reviewed by Alloul which show that the hyperfine coupling constants do not change with doping and that there is a single quantum fluid which can be observed by monitoring the Knight shift on either ⁶³Cu or ¹⁷O nuclei. X-ray absorption spectroscopy reviewed by Sawatzky also offers direct evidence that distinct electronic configurations of formal valence Cu²⁺ and Cu³⁺ appear upon doping. This shows that the Coulomb repulsion continues to be relevant on the low energy scale in the doped materials just as it is in the Mott insulators. The BCS theory of superconductivity, which is so successful for th...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Contents
• An introduction to superconductivity and passive microwave devices
• Flux quantisation; mixed states; Josephson effect; SQUIDs
• Critical currents in cuprate superconductors
• Chemistry of oxide superconductors
• Transition metal oxides and high temperature superconductors
• Optical properties of insulators and metals with copper oxide planes
• Experimental studies of magnetic properties of cuprates
• The spin polaron model and the comparison with liquid helium
• Strong correlations and high temperature superconductivity
• Introduction to the theory of strongly correlated electrons
• The quantum chemistry view of high temperature superconductors