Josephson tunneling between a conventional superconductor (Pb) and YBa2Cu3O7-δ

doi:10.1016/0921-4534(94)91354-4

Physica C: Superconductivity

Volumes 235–240, Part 1, December 1994, Pages 225-228

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Abstract

The symmetry of the order parameter in the high T_c cuprates can be probed by investigation of its phase using various squid configurations. Even more simply, an investigation of the overlap of the pair wavefunction of a conventional superconductor with a high T_c cuprate should reveal the symmetry of the cuprate. We have been studying this overlap by Josephson tunneling (tunneling as opposed to SNS or weak link) between Pb and YBa₂Cu₃O_7-δ. The observation of a Josephson coupling in the c-axis implies the order parameter in the cuprate is not strictly d_x2_-y2 symmetry. Measurements of the magnetic field dependence of the Josephson current I_c(B) allow a direct, d.c. measurement of the low temperature penetration depth. Studies have been performed on twinned and untwinned single crystals and thin films.

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Oxygen-controlled transition from tunnel-like to a weak-link behavior in YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7-δ</inf>/YBa<inf>2</inf>CoCu <inf>2</inf>O<inf>y</inf>/YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7-δ</inf> wedge-edge junctions
1996, Physica C: Superconductivity and its Applications
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^∗: In collaboration with A.G. Sun, L. Paulius, D. Gajewski, S. Han, A. Katz and M.B. Maple

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Josephson tunneling between a conventional superconductor (Pb) and YBa2Cu3O7-δ

Abstract

J. Phys. Chem. Solids

Introduction to Superconductivity

Phys. Rev. Lett.

Josephson tunneling between a conventional superconductor (Pb) and YBa₂Cu₃O_7-δ