Guideline for Developing High-density Recording Media Based on Magnetic Cluster Analysis

We examined the relationship between media cluster size distribution and signal quality to obtain a guideline for developing high-density recording media. Both spin-stand measurements and micromagnetics simulations were used. The cluster size distribution and SNR of various recording media were evaluated, and the relationship between the two was analyzed using multiple regression analysis. The results demonstrate that the media SNR could be quantitatively estimated from the cluster size distribution (both average sizes and size deviations). Although reducing either the average size or the size deviation was effective in terms of improving theSNR, the impact of the average was much larger. On the other hand, we also found that the effect of size deviation increased for the smaller average-sized media. We concluded that providing the guidelines for each individual developing medium is a key step and that the proposed analysis method is therefore effective.