Magnetic DynamicsVariation Induced by the MeissnerEffect in Superconductor/Ferromagnet Heterostructures

Magnetic dynamics in superconductor (S)/ferromagnet (F)/superconductor (S) heterostructures is a focal spot in spintronics, but its physical origin remains debated. In this study, we fabricated S/F/S and S/Pt/F/Pt/S heterostructures to explore the impact of S layers on the magnetization dynamics of the F layer. We found that the ferromagnetic resonance field of the F layer shifted to lower fields as the temperature declined below the superconducting critical temperature <i>T</i>_c. Additionally, the inhomogeneous linewidth μ₀Δ<i>H</i>₀ broadened below <i>T</i>_c. Despite the insertion of thick platinum layers to block spin currents at the S/F interface, the resonance field shift persisted. We hypothesize that these variations result from the Meissner effect, which causes the S layers to generate an additional spatially inhomogeneous magnetic field below <i>T</i>_c. This leads to observed resonance field shifts and μ₀Δ<i>H</i>₀ broadening. Our findings clarify the origins of superconductivity-induced resonance field shifts and may advance superconducting spintronic devices for information processing.