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Point Contact Spectra on YBa$_2$Cu$_3$O$_{7-x}$/La$_{0.7}$Ca$_{0.3}$MnO$_3$ bilayers

Samanta Piano·Fabrizio Bobba·Adele De Santis·Filippo Giubileo·Alessandro Scarfato·Anna Maria Cucolo
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Abstract

We present conductance characteristics of point contact junctions realized between a normal Pt-Ir tip and YBa$_2$Cu$_3$O$_{7-x}$/La$_{0.7}$Ca$_{0.3}$MnO$_3$ (YBCO/LCMO) bilayers. The point contact characteristics show a zero bias conductance peak, as a consequence of the formation of Andreev bound states at the YBCO Fermi level. The temperature evolution of the spectra reveals a depressed zero bias peak and a reduced superconducting energy gap, both explainable in terms of spin polarization effects due to the LCMO layer.

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Samanta Piano, Fabrizio Bobba, Adele De Santis, Filippo Giubileo, Alessandro Scarfato, Anna Maria Cucolo. 2006-01-30. Point Contact Spectra on YBa$_2$Cu$_3$O$_{7-x}$/La$_{0.7}$Ca$_{0.3}$MnO$_3$ bilayers. https://doi.org/10.1088/1742-6596%2F43%2F1%2F273

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