What Does Instrinsic Josephson Coupling Say about the Pairing Symmetry in the Cuprates?
نویسندگان
چکیده
Measurements of the c-axis properties of the cuprate superconductors show anomalous behavior in both normal and superconducting states. In particulaL there is strong evidence that pairs of CuO2 planes in neighboring unit cells act as Josephson junctions below the critical temperature Tr We present a theory based on incoherent transport Mong the c-axis which naturally reproduces the anisotropic normal-state resistivity and the superconducting-state Josephson coupling. Applying this theory to YBa2Cu3OT-~ (YBCO), we make quantitative predictions for the strength and temperature dependence of the Josephson coupling as well as the variation of Te with disorder. Beyond the expected low-temperature behavior, the Josephson critical current does not make a clean separation between sand d-wave superconductors, but the disorder-induced Tr variation does. Further experimental and theoretical work along these lines may therefore help determine the order parameter symmetry in the cuprates.
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