It is proposed to measure and analyze the electgrical conductivity and Hall effect in high-temperature superconducting compounds. The work will begin with studies of YBa2Cu3O7-s untwinned single crystals as a function of Temperature, magnetic field and the Oxygen-Content parameter s, and will then be extended to other compounds as high-quality samples become available. These measurements will test the adequacy of current theory to explain the behavior of high-temperature superconductors (HTSCs) and should help one to develop a better theory of HTSC.
