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Phase-sensitive Evidence for d-wave Pairing Symmetry in Electron-doped Cuprate Superconductors

C. C. Tsuei·J. R. Kirtley
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Abstract

We present phase-sensitive evidence that the electron-doped cuprates Nd1.85Ce0.15CuO4-y (NCCO) and Pr1.85Ce0.15CuO4-y (PCCO) have d-wave pairing symmetry. This evidence was obtained by observing the half-flux quantum effect, using a scanning SQUID microscope, in c-axis oriented films of NCCO or PCCO epitaxially grown on tricrystal [100] SrTiO3 substrates designed to be frustrated for a d(x2-y2) order parameter. Samples with two other configurations, designed to b unfrustrated for a d-wave superconductor, do not show the half-flux quantum effect.

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C. C. Tsuei, J. R. Kirtley. 2000-05-15. Phase-sensitive Evidence for d-wave Pairing Symmetry in Electron-doped Cuprate Superconductors. https://doi.org/10.1103/physrevlett.85.182

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