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c-Axis Twist Bi2Sr2CaCu2O(8+delta) Josephson Junctions: A New Phase-Sensitive Test of Order Parmaeter Symmetry

R. A. Klemm·C. T. Rieck·K. Scharnberg
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Abstract

Li et al. found that the critical current density JcJ across atomically clean c-axis twist junctions of Bi2Sr2CaCu2O(8+x) is the same as that of the constituent single crystal, JcS, independent of the twist angle phi0, even at Tc. We investigated theoretically if a dx2-y2-wave order parameter might twist by mixing in dxy components, but find that such twisting cannot possibly explain the data near to Tc. Hence, the order parameter contains an s-wave component, but not any dx2-y2-wave component. In addition, the c-axis Josephson tunneling is completely incoherent. We also propose a c-axis junction tricrystal experiment which does not rely upon expensive substrates.

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R. A. Klemm, C. T. Rieck, K. Scharnberg. 1999-02-19. c-Axis Twist Bi2Sr2CaCu2O(8+delta) Josephson Junctions: A New Phase-Sensitive Test of Order Parmaeter Symmetry. https://arxiv.org/abs/cond-mat/9902271

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