The High Temperature Superconductivity in Cuprates

Abstract

We discuss the high-temperature superconductivity in copper oxide ceramics. We propose an effective Hamiltonian to describe the dynamics of electrons or holes injected into the copper oxide layers. We show that our approach is able to account for both the pseudogap and the superconductivity gap. For the hole-doped cuprates we discuss in details the underdoped, optimal doped, and overdoped regions of the phase diagram. In the underdoped region we determine the doping dependence of the upper critical magnetic field, the vortex region, and the discrete states bounded to the core of isolated vortices. We explain the origin of the Fermi arcs and Fermi pockets. Moreover, we discuss the recently reported peculiar dependence of the specific heat on the applied magnetic field. We determine the critical doping where the pseudogap vanishes. We find that in the overdoped region the superconducting transition is described by the conventional d-wave BCS theory. We discuss the optimal doping region and the crossover between the underdoped region and the overdoped region. We also discuss briefly the electron-doped cuprate superconductors.