About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
Applied Superconductivity
Paper
Tunneling spectroscopy of high-Tc superconductors
Abstract
We have performed tunneling spectroscopy experiments on different kinds of high-temperature superconductors (HTS) and different types of junctions. Firstly, spectra were taken on surfaces of YBa2Cu3O7-δ (YBCO) thin films and Nd1.85Ce0.15CuO4-γ (NCCO) single crystals by low-temperature scanning tunneling microscopy/spectroscopy (LTSTM/S) in a superconductor-insulator-normal metal (SIN) configuration. Second, the tunneling spectra of grain-boundary junctions (GBJs) fabricated on bicrystal substrates were measured for the materials YBCO, La1.85Sr0.15CuO4-δ (LSCO), Bi2Sr2Ca-Cu2O8 + δ (BSCCO) and NCCO in a SIS configuration. The characteristics of the spectra in both systems could be related to the symmetry of the order parameter in the superconducting electrode(s). In particular, a zero bias conductance peak (ZBCP) was observed only in systems with a d-wave symmetry, but was completely absent in the s-wave system NCCO. © 1999 Elsevier Science Ltd. All rights reserved.