Critical Currents and Superconductivity

Samir Khene

Preface. Superconducting state. History of the superconductivity. Definition of a superconducting material. Meissner effect. Destruction of the superconductivity. Description of the superconducting state. Electronic specific heat. Electromagnetic absorption. Isotopic effect. Flux quantification. Josephson effects. References. Basis models. London model. Phenomenological theory of Ginzburg-Landau. BCS theory. References. High-Tc superconductor characteristics. Introduction. Cristallographic structures. Artificial multilayers. Physico-chemical properties. Elaboration process. References. Phenomenological theories of the anisotropic superconductors. Anisotropic Ginzburg-Landau model. Lawrence-Doniach model. References. Dynamic of vortices. Hysteresis origin in the magnetization curves. Breaking current of the Cooper pairs. Pinning force. Flux flow. Bean model. Flux creep. Thermally assisted flux flow. Irreversibility line. Magnetic instabilities. References. Interactions vortex-vortex, vortex defect and vortex-spin. Introduction. Elasticity theory of the vortices lattice. Different approaches of the vortices trapping. Critical currents. Lock-in transition. Pinning theory of Feigel’man, Geshkenbein et Larkin. Superconductivity and ferromagnetism Appendice. Demagnetizing fields. Physical quantities in SI and c.g.s.gauss systems. Some useful equations. References.