Spectroscopy Of High Tc Superconductors

Despite ten years of intensive research, many questions remain unanswered concerning the nature of the electronic structure (Fermi vs non-Fermi liquid) and mechanisms of superconductivity. Spectroscopy of High-Tc Superconductors, A Theoretical View provides a current, comprehensive review of the experimental results and theoretical interpre

This book mainly focuses on the study of the high-temperature superconductor Bi2Sr2CaCu2O8 by vacuum, ultra-violet, laser-based, angle-resolved photoemission spectroscopy (ARPES). A new form of electron coupling has been identified in Bi2212, which occurs in the superconducting state. For the first time, the Bogoliubov quasiparticle dispersion with a clear band back-bending has been observed with two peaks in the momentum distribution curve in the superconducting state at a low temperature. Readers will find useful information about the technique of angle-resolved photoemission and the study of high-temperature superconductors using this technique. Dr. Wentao Zhang received his PhD from the Institute of Physics at the Chinese Academy of Sciences.

CONTENTS: Weak Coupling Theory of High Temperature Superconductors; Investigations of a Few Novel Series of Thallium Cuprate Superconductors Showing Possible Change in the Sign of Charge Carriers with Composition; Some Structural & Chemical Aspects of the Bi-Pb-Sr-Ca-Cu-O System; High Magnetic Field Studies of High Temperature Superconductors; Fabrication of Bi-Sr-Ca-Cu Oxide Superconductors with Controlled Numbers of Cu-0 Layers; Characterization of High Temperature Superconductors by High Excitation Spectroscopies; Mossbauer Spectroscopy of High Temperature Superconductors; RVB & Related Theories of HTSC; Fabrication of 107k Superconducting Films & Their Normal State Transport Properties; Ion Beam Analysis of High T Superconductors; Thermal Conductivity of High Temperature Superconductor; A New Theoretical Approach to Electron Pairing And Uperconductivity in High T Superconductors; High Resolution Polarized X-Ray Absorption Spectroscopy: Symmetry of the Hole States in High-T Superconductors; Phase Diagrams in the Y-Ba-Cu-O System & Crystal Growth of Ybco Superconductors; Index.

This book mainly focuses on the study of the high-temperature superconductor Bi2Sr2CaCu2O8+δ (Bi2212) and single-layer FeSe film grown on SrTiO3 (STO) substrate by means of angle-resolved photoemission spectroscopy (ARPES). It provides the first electronic evidence for the origin of the anomalous high-temperature superconductivity in single-layer FeSe grown on SrTiO3 substrate. Two coexisted sharp-mode couplings have been identified in superconducting Bi2212. The first ARPES study on single-layer FeSe/STO films has provided key insights into the electronic origin of superconductivity in this system. A phase diagram and electronic indication of high Tc and insulator to superconductor crossover have been established in the single-layer FeSe/STO films. Readers will find essential information on the techniques used and interesting physical phenomena observed by ARPES.

Since the discovery in 1986 of high temperature superconductors by J. G. Bednorz and K. A. Müller, a considerable progress has been made and several important scientific problems have emerged. Within this NATO Advanced Study Institute our intention was to focus mainly on the controversial topic of the symmetry of the superconducting gap and given the very short coherence length, the role of fluctuations. The Institute on ‘The Gap Symmetry and Fluctuations in High- Superconductors’ took place in the “Institut d’Etudes Scientifiques de Cargèse” in Corsica, France, between 1 - 13 September 1997. The 110 participantsfrom 18 countries (yet 30 nationalities) including 23 full time lecturers, have spent two memorable weeks in this charming Mediterranean resort. All lecturers were asked to prepare pedagogical papers to clearly present the central physical idea behind specific model or experiment. The better understanding of physics of high temperature superconductivity is certainly needed to guide the development of applications of these materials in high and weak current devices.

The first part of these proceedings contains the invited lectures which aim to unify and summarize briefly the systematic knowledge and latest developments in the entire spectrum of high Tc superconductivity, including the phenomenological and microscopic theory on HTS, crystal structures and defects, the fabrication of high Tc superconductors, physical properties of HTSC, tunneling junctions and electronics of HTSC, etc. The second part consists of the abstracts of all reports given at the seminar sessions.

Authored by many of the world's leading experts on high-Tc superconductivity, this volume presents a panorama of ongoing research in the field, as well as insights into related multifunctional materials. The contributions cover many different and complementary aspects of the physics and materials challenges, with an emphasis on superconducting materials that have emerged since the discovery of the cuprate superconductors, for example pnictides, MgB2, H2S and other hydrides. Special attention is also paid to interface superconductivity. In addition to superconductors, the volume also addresses materials related to polar and multifunctional ground states, another class of materials that owes its discovery to Prof. Müller's ground-breaking research on SrTiO3.