Optimizing spin pumping in Yttrium Iron Garnet/Platinum bilayers under varying oxygen pressure

Abstract

Here, we study the influence of magnetic properties on the spin-pumping effect of the Yttrium Iron Garnet/Platinum (YIG/Pt) bilayer. YIG films were deposited by pulsed laser deposition under variable oxygen pressures. Using broadband ferromagnetic resonance techniques, the magnetic properties of the YIG films were measured. We analyzed the spin-pumping effect in these films by measuring damping changes in samples with and without Pt layers, enabling the calculation of spin-mixing conductance. Experimental results show that films prepared at high oxygen pressure exhibit lower magnetization and reduced spin pumping, ${\alpha }_{sp}$, leading to a decreased spin mixing conductance, $g^{\uparrow \downarrow }$. We report a variation in $g^{\uparrow \downarrow }$ ranging from $4.2\times 10^{18}$ to $15.6\times 10^{18},{\text{m}}^{-2}$. These findings underscore the sensitivity of spin transport properties to deposition parameters in YIG-based spintronic devices.