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Register a new userSuperconducting triplet pairing in Al/Al$_mathbf{2} $O$_mathbf{3} $/Ni/Ga junctions
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Ni/Ga bilayers are a versatile playground for exploring the competition of the strongly antagonistic ferromagnetic and superconducting phases. Systematically characterizing this competitions impact on highly ballistic Al/Al$_2 $O$_3 $/Ni/Ga junctions transport properties from both the experimental and theoretical viewpoints, we identify novel conductance peak structures, which are caused by superconducting triplet pairings at the Ni/Ga interface, and which are widely adjustable through the Ni-Ga thickness ratio. We demonstrate that these conductance anomalies persist even in the presence of an in-plane magnetic field, which provides -- together with the detection of the paramagnetic Meissner effect in Ga -- the clear experimental evidence that the observed conductance features serve indeed as the triplet pairings unique transport fingerprints. Our work demonstrates that Ni/Ga bilayers have a strong potential for superconducting spintronics applications, in particular for triplet-pairing engineering.
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