High temperature superconductors (HTS) have many properties that differ from conventional superconductors, the anisotropic energy gap notable among them. Josephson tunneling provides a phase sensitive technique to examine the energy gap and some measurements in HTS have suggested a zero energy gap along particular directions indicating a different, d-wave, electron- electron pairing mechanism compared to s-wave pairing in conventional superconductors. This research will investigate the transport properties across a HTS and conventional superconductor interface. Three experiments are planned: to determine how electrons are reflected by the interface; to study how electrons or electron pairs behave after tunneling through the interface; and to investigate induced superconductivity in a normal metal film in close proximity to the HTS. Student and post doctoral fellow education will be supported and will provide trained professionals in the superconductor and related semiconductor industries. %%% High temperature superconductors (HTS) have important fundamental properties that differ from conventional low temperature superconductors. Current transport that is uniform with direction in conventional superconductors varies with direction in crystalline HTS in response to a fundamental anisotropy. The goal of this research is to investigate the origin of these anisotropic properties. In particular, this research will improve our understanding of how conventional low temperature superconductors and normal metals can be connected to the HTS and how current will be transported across that interface. Such knowledge is important for the introduction and improvement of superconducting devices in the electronics, telecommunication, and medical diagnostic industries. Professional edu cation and training will be provided for students and a post doctoral fellow. ***
