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Superconducting current-phase relation in Nb/Au/(001)YBa2Cu3Ox heterojunctions

P. V. Komissinski·E. Il'ichev·G. A. Ovsyannikov·S. A. Kovtonyuk·M. Grajcar·Z. Ivanov·Y . Tanaka·N. Yoshida·S. Kashiwaya
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Abstract

We probe directly the superconducting current-phase relations (CPR) of Nb/Au/(001) YBa2Cu3Ox heterojunctions prepared in epitaxial c-axis oriented YBa2Cu3Ox (YBCO) thin films. The measurements are performed by a single-junction interference experiment. Atomic Force Microscope observations and estimations made from I-V characteristics confirm the c-axis current transport. No deviation of the current-phase relation from a sinusoidal shape has been found within the experimental accuracy. Possible reasons of the absence of the second harmonic in the CPR due to a second order tunneling are discussed.

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P. V. Komissinski, E. Il'ichev, G. A. Ovsyannikov, S. A. Kovtonyuk, M. Grajcar, Z. Ivanov, Y . Tanaka, N. Yoshida, S. Kashiwaya. 2000-08-07. Superconducting current-phase relation in Nb/Au/(001)YBa2Cu3Ox heterojunctions. https://arxiv.org/abs/cond-mat/0008077

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