Effect of quartic anisotropy term on read/write properties of perpendicular recording media

Thermal stability of the magnetic recording media is the most important key factor to realize high density magnetic recording. The uniaxial quartic anisotropy term (K₂) is expected to be effective to enhance the energy barrier for magnetization reversals without significant increase in the switching field. Theoretical analysis shows that the thermal stability can be increased by K₂ without increasing the switching field when K₂/K₁ < 0.25, but the switching field is increased when the angle between the applied field and the easy axis (field angle) is larger than 30° independent of the K₂ value. In this paper, we simulate the recording process of the dual-layer perpendicular media with K₂ term using micromagnetic computer simulation, and obtain the read/write properties to investigate the effect of the K₂ term on write operation.