Transport and spectroscopic properties of superconductor - ferromagnet - superconductor junctions of $La_{1.9}Sr_{0.1}CuO_4$ - $La_{0.67}Ca_{0.33}MnO_3$ - $La_{1.9}Sr_{0.1}CuO_4$

Gad Koren; Tal Kirzhner

doi:10.1103/PhysRevB.84.134517

paper

Transport and spectroscopic properties of superconductor - ferromagnet - superconductor junctions of $L a_{1.9} S r_{0.1} C u O_{4}$ - $L a_{0.67} C a_{0.33} M n O_{3}$ - $L a_{1.9} S r_{0.1} C u O_{4}$

arXiv:1107.0806 · doi:10.1103/PhysRevB.84.134517

Abstract

Transport and Conductance spectra measurements of ramp-type junctions made of cuprate superconducting $L a_{1.9} S r_{0.1} C u O_{4}$ electrodes and a manganite ferromagnetic $L a_{0.67} C a_{0.33} M n O_{3}$ barrier are reported. At low temperatures below $T_{c}$ , the conductance spectra show Andreev-like broad peaks superposed on a tunneling-like background, and sometimes also sub-gap Andreev resonances. The energy gap values $Δ$ found from fits of the data ranged mostly between 7-10 mV. As usual, the gap features were suppressed under magnetic fields but revealed the tunneling-like conductance background. After field cycling to 5 or 6 T and back to 0 T, the conductance spectra were always higher than under zero field cooling, reflecting the negative magnetoresistance of the manganite barrier. A signature of superparamagnetism was found in the conductance spectra of junctions with a 12 nm thick LCMO barrier. Observed critical currents with barrier thickness of 12 nm or more, were shown to be an artifact due to incomplete milling of one of the superconducting electrodes.

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Transport and spectroscopic properties of superconductor - ferromagnet - superconductor junctions of $L a_{1.9} S r_{0.1} C u O_{4}$ - $L a_{0.67} C a_{0.33} M n O_{3}$ - $L a_{1.9} S r_{0.1} C u O_{4}$

Abstract

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Transport and spectroscopic properties of superconductor - ferromagnet - superconductor junctions of La1.9​Sr0.1​CuO4​ - La0.67​Ca0.33​MnO3​ - La1.9​Sr0.1​CuO4​

Abstract

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Cited by in corpus (2)

Transport and spectroscopic properties of superconductor - ferromagnet - superconductor junctions of $L a_{1.9} S r_{0.1} C u O_{4}$ - $L a_{0.67} C a_{0.33} M n O_{3}$ - $L a_{1.9} S r_{0.1} C u O_{4}$