Micromagnetic Simulations of Cluster-Pinned Recording Media

Cluster-pinned recording media, consisting of discrete clusters exchange-coupled to a continuous hard layer, were modeled to investigate their suitability for high-density data storage. The pinning field due to the clusters was determined by modeling domain wall motion in the continuous layer. Larger clusters, a thinner continuous layer, and increased saturation magnetization of the clusters all increased the pinning field. Different cluster shapes had no effect on the pinning field. Varying the cluster density, while maintaining the total surface area, significantly increased the pinning field once the cluster density dropped below a certain level.