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arXiv · 1905.07683

Long-range triplet proximity effect in multiply connected ferromagnet-superconductor hybrids

Abstract

Applying the linearized Usadel equations, we consider the nucleation of superconductivity in multiply connected mesoscopic superconductor/ferromagnet (S/F) hybrids such as a thin superconducting ring on a ferromagnet with a uniform in-plane magnetization M and a spin-active S/F interface. We demonstrate that the exchange field in F provokes a switching between superconducting states with different vorticities which may increase the critical temperature ( Tc ) of the superconductor in a magnetic field. We study the interplay between oscillations in Tc due to the Little--Parks effect and oscillations in Tc induced by the exchange field. Furthermore, we analyse the influence of long-range spin-triplet correlations on the switching between different vorticities.

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A. V. Samokhvalov, J. W. A. Robinson, A. I. Buzdin. 2019-05-19. Long-range triplet proximity effect in multiply connected ferromagnet-superconductor hybrids. https://doi.org/10.1103/physrevb.100.014509

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