Abrikosov vortex nucleation and its detrimental effect on superconducting spin pumping in Pt/Nb/Ni80Fe20/Nb/Pt proximity structures

We report Abrikosov vortex nucleation in $\mathrm{Pt}/\mathrm{Nb}/{\mathrm{Ni}}₈₀{\mathrm{Fe}}₂₀/\mathrm{Nb}/\mathrm{Pt}$ proximity-coupled structures under oblique ferromagnetic resonance that turns out to be detrimental to superconducting spin pumping. By measuring an out-of-plane field-angle ${\ensuremath{\theta}}_H$ dependence and comparing with Pt-absent control samples, we show that as ${\ensuremath{\theta}}_H$ increases, the degree of enhancement (suppression) of spin pumping efficiency in the superconducting state for the Pt-present (Pt-absent) sample diminishes and it reverts to the normal state value at ${\ensuremath{\theta}}_H={90}^{\ensuremath{\circ}}$. This can be explained in terms of a substantial out-of-plane component of the resonance field for the ${\mathrm{Ni}}₈₀{\mathrm{Fe}}₂₀$ layer (with in-plane magnetization anisotropy and high aspect ratio) that approaches the upper critical field of the Nb, turning a large fraction of the singlet superconductor volume into the normal state.