Strong-Coupling Theory of High-Temperature Superconductivity

High-temperature superconductivity has transformed the landscape of solid state science, leading to the discovery of new classes of materials, states of matter, and concepts. However, despite being over a quarter of a century since its discovery, there is still no single accepted theory to explain its origin. This book presents one approach, the strong-coupling or bipolaron theory, which proposes that high-temperature superconductivity originates from competing Coulomb and electron-phonon interactions. The author provides a thorough overview of the theory, describing numerous experimental observations, and giving detailed mathematical derivations of key theoretical findings at an accessible level. Applications of the theory to existing high-temperature superconductors are discussed, as well as possibilities of liquid superconductors and higher critical temperatures. Alternative theories are also examined to provide a balanced and informative perspective. This monograph will appeal to advanced researchers and academics in the fields of condensed matter physics and quantum-field theories.Preface; 1. Coulomb and Frohlich interactions; 2. Small polarons; 3. Inverse-coupling expansion technique; 4. High-temperature superconductivity; 5. Converting boson-fermion mixtures; 6. Superconductivity from repulsion: theoretical constraints; 7. Theory and experiment: confirmed predictions; 8. Experiments explained: normal state; 9. Experiments explained: superconducting state; 10. Further predictions; Index.