Many experiments on high-temperature superconductors have shown paramagnetic behavior when the sample is field cooled. The paramagnetism was attributed to a d-wave order parameter creating pi-junctions in the samples. However, the same effect was later discovered in traditional low-temperature superconductors and conventional Josephson-junction arrays which are s wave. By simulating both conven...

Bellemans and De Leener) have studied the ground state energy of an electron gas moving in a lattice of positive charges. This picture is ex~ pected to correspond roughly to actual metals or metallic solutions. The purpose of this paper is to extend their treatment to a study of spin paramagnetism. The magnetic susceptibility of the system is determined by the change in energy as the electron s...

We study the magnetic-field-induced breakdown of superconductivity in nm-scale metal grains having a mean electron level spacing d . D̃ (bulk gap). Using a generalized variational BCS approach that yields good qualitative agreement with measured spectra, we argue that Pauli paramagnetism dominates orbital diamagnetism, as in the case of thin films in a parallel magnetic field. However, the first...

We investigate low temperature (T ) properties of three classical quantum statistics models: (I) the Fermi-Dirac equation, (II) the Boltzman equation, and (III) the Bose-Einstein equation. It is widely assumed that each of these equations is valid for all T > 0. For each equation we prove that this assumption leads to erroneous predictions as T → 0. Our approach to correct these errors gives ne...

Aspects of the normal state phase of copper oxide planes in high Tc superconductors. Abstract We examine various aspects of the normal state phase of CuO 2 planes in the high Tc superconductors. In particular, within the context of the three band Hubbard model, we study as a function of doping the competition between a charge density wave phase induced by oxygen breathing modes, antiferromagnet...