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Possible d+id scenario in La_{2-x}Sr_{x}CuO_4 by point-contact measurements

D. Daghero·R. S. Gonnelli·G. A. Ummarino·V. A. Stepanov
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Abstract

We analyze the results of point-contact measurements in La_{2-x}Sr_{x}CuO_{4} (LSCO) previously reported as a clear evidence of the separation between gap and pseudogap in this copper oxide. Here we show that, in addition to this, the conductance curves of our point-contact junctions -- showing clear Andreev reflection features -- can be interpreted as supporting a nodeless d_{x^2-y^2}+id_{xy}-wave symmetry of the gap in LSCO. The results of our analysis, in particular the doping dependence of the subdominant d_{xy} gap component, are discussed and compared to the predictions of different theoretical models.

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D. Daghero, R. S. Gonnelli, G. A. Ummarino, V. A. Stepanov. 2002-07-18. Possible d+id scenario in La_{2-x}Sr_{x}CuO_4 by point-contact measurements. https://doi.org/10.1142/s0217979203016376

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