Möller, C. H. Grundler, D. Kronenwerth, O. Heyn, C. Heitmann, D.
Published in
Journal of Superconductivity
We report on magnetotransport experiments performed at 4.2 K on hybrid structures consisting of a metal and a mesoscopic two-dimensional electron system in an InAs/InGaAs heterostructure. The devices were fabricated using cleaved-edge overgrowth. We find that they exhibit an extraordinary magnetoresistance effect (EMR) which is most pronounced in t...
Pavuna, Davor
Published in
Journal of Superconductivity
We briefly discuss some electronic and transport “anomalies” observed in superconducting perovskites. In particular we consider: (i) the complex electronic (and crystallographic) phase diagram, (ii) the symmetry of the gap with a special emphasis on the evidence for s-wave component in various experiments, and (iii) non-Fermi-liquid transport in su...
Pavuna, Davor
Published in
Journal of Superconductivity
Following introductory remarks on the “future history” of superconductivity, I discuss several discrepances concerning doping dependence of the “pseudogap” and open questions across the complex electronic phase diagram. I argue that once we understand the fundamentals, we will eventually be able to fully exploit the richness of the phase diagram of...
Pavuna, D. Vobornik, I. Margaritondo, G.
Published in
Journal of Superconductivity
We summarize some of the main results on photoemission spectroscopy in the field of high-Tc superconductivity, beginning with a discussion of several open questions. We then briefly analyze our experiments that illustrate the role of doping and of intentionally introduced disorder (by electron bombardment) in Bi2Sr2CaCu2O8+x single crystals.
Poirot, Nathalie Gervais, François
Published in
Journal of Superconductivity
Electrical resistivity of La2NiO4+δ single crystals has been investigated. Results showed several anomalies that are related to the onset of spin and charge ordering, either static or dynamic.
Mena, J. Miranda de León, J. Mustre Bishop, A. R.
Published in
Journal of Superconductivity
We have performed an exact diagonalization of a many body Hamiltonian that includes electron correlations and electron–phonon interactions. Electronic and phononic parameters entering in the Hamiltonian were chosen for the cluster O(4)—Cu–O(4) cluster in YBa2Cu3O7. Electronic and phononic degrees of freedom are coupled through the bare electron hop...
Oyanagi, H. Saini, N. L. Tsukada, A. Naito, M.
Published in
Journal of Superconductivity
Local lattice anomalies in optimally doped T-(La,Sr)2CuO4 single crystal like thin films (Tc = 43.4 K) grown by molecular-beam epitaxy have been studied by the in-plane polarized Cu K-edge extended X-ray absorption fine structure (EXAFS). The results indicate temperature-dependent local atomic displacements which are anomalous at the Tc and below a...
Prellier, W. Padhan, P. Mercey, B.
Published in
Journal of Superconductivity
Magnetic multilayers of (SrRuO3)m(SrMnO3)n were grown artificially using the pulsed laser deposition technique on (001)-oriented SrTiO3 substrates. The temperature and magnetic field dependent reisistivity of the superlattices consisting of ferromagnetic (FM) SrRuO3 and antiferromagnetic (AFM) SrMnO3 are studied as a function of the SrRuO3 unit cel...
Rigamonti, A. Lascialfari, A. Romanò, L. Varlamov, A. Zucca, I.
Published in
Journal of Superconductivity
The fluctuation-induced diamagnetism (FD) above the transition temperature Tc is studied through the isothermal field-dependence of the diamagnetic magnetization Mdia. While for T ≈ Tc and H→0 one has –Mdia ∝ (H)1/2,on increasing field an upturn occurs and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts}...
Park, Y. W. Kim, B. H. Kim, J. S. Kim, D. C. Kim, Boggi
Published in
Journal of Superconductivity
We have investigated the high-temperature thermoelectric power (TEP) of La2−xSrxCuO4 (0.05 ≤ x ≤ 0.35) and Bi1−xSrxMnO3 (0.5 ≤ x ≤ 0.8) up to 700 K. Based on the TEP results we have discussed the phase transitions on each case. In the case of high-TC cuprates, La2−xSrxCuO4 (0.05 ≤ x ≤ 0.35), the TEP shows different temperature dependences in three ...
