Sputtering Deposition and Magnetic Properties of Co_xFe_1-x Thin Films

Understanding and controlling magnetic damping in metallic ferromagnets is essential for advancing spintronic and quantum devices [1-2]. Recent studies have demonstrated the achievement of ultralow intrinsic damping in Co_0.25Fe_0.75 thin films with Cu(3 nm)/Ta(3 nm) seed and capping layers [1]. However, the effect of interfaces on the magnetic damping of Co_xFe_1-x films remains to be fully understood. Here we report sputtering deposition of CoₓFe₁₋ₓ thin films (x: 0, 0.25, and 1) with varied seed and capping layers on Si substrates. Small-angle X-ray reflectivity and X-ray diffraction measurements have confirmed the structure of the grown multilayers. Magnetic hysteresis loops measured by vibrating sample magnetometry have revealed the in-plane magnetic anisotropy and the effect of interfaces on the saturation magnetization of CoₓFe₁₋ₓ films. Time-resolved magneto-optical Kerr effect (TR-MOKE) measurements provide valuable information on magnetic damping.