Isolation of proximity-induced triplet pairing channel in a superconductor/ferromagnet spin valve

P. V. Leksin; N. N. Garifyanov; A. A. Kamashev; A. A. Validov; Ya. V. Fominov; J. Schumann; V. Kataev; J. Thomas; B. Büchner; I. A. Garifullin

doi:10.1103/physrevb.93.100502

arXiv · 1510.05392

Isolation of proximity-induced triplet pairing channel in a superconductor/ferromagnet spin valve

P. V. Leksin·N. N. Garifyanov·A. A. Kamashev·A. A. Validov·Ya. V. Fominov·J. Schumann·V. Kataev·J. Thomas·B. Büchner·I. A. Garifullin

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Abstract

We have studied the proximity-induced superconducting triplet pairing in CoO$_x$/Py1/Cu/Py2/Cu/Pb spin-valve structure (where Py = Ni$_{0.81}$Fe$_{0.19}$). By optimizing the parameters of this structure we found a triplet channel assisted full switching between the normal and superconducting states. To observe an "isolated" triplet spin-valve effect we exploited the oscillatory feature of the magnitude of the ordinary spin-valve effect $ΔT_c$ in the dependence of the Py2-layer thickness $d_{Py2}$. We determined the value of $d_{Py2}$ at which $ΔT_c$ caused by the ordinary spin-valve effect (the difference in the superconducting transition temperature $T_c$ between the antiparallel and parallel mutual orientation of magnetizations of the Py1 and Py2 layers) is suppressed. For such a sample a "pure" triplet spin-valve effect which causes the minimum in $T_c$ at the orthogonal configuration of magnetizations has been observed.

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P. V. Leksin, N. N. Garifyanov, A. A. Kamashev, A. A. Validov, Ya. V. Fominov, J. Schumann, V. Kataev, J. Thomas, B. Büchner, I. A. Garifullin. 2016-03-30. Isolation of proximity-induced triplet pairing channel in a superconductor/ferromagnet spin valve. https://doi.org/10.1103/physrevb.93.100502

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