Effect of Spacer Layer Thickness on the Magnetic Properties of $({\hbox {SnO}}_{2}/{\hbox {Cu\textendash Zn}} {\hbox {Ferr\ite}})_{\rm n}$ Multilayers

Multilayers (ML) of SnO₂ and Cu-Zn Ferrite were deposited by rf-sputtering. The effect of spacer layer (SnO₂) thickness on the structural and magnetic properties of ML were studied. The disorder and strain in the system is found to increase with increasing spacer layer thickness. The interlayer coupling is found to decrease with increasing SnO₂ layer thickness. The FMR intensity, magnetization and the exchange coupling strength initially increases then decreases with increasing SnO₂ thickness. This behavior may be attributed to the oscillation in the exchange coupling across the non magnetic layer due to quantum interference of the electron waves reflected from the interfaces. The ML exhibit uniaxial anisotropy and the ML are found to be more homogeneous when the film normal is at an angle of 40° with the applied field. Decreasing magnetic moment and increasing resonance field at low temperatures indicated the presence of antiferromagnetic interactions in these ML.