Temperature dependence of thermal stability in longitudinal media

The temperature dependence of the thermal stability factor (K_uV/k_BT) and the remanent coercivity are measured as a function of temperature from 20°C to 120°C. A significant decrease with temperature in both the thermal stability factor and remanent coercivity were observed due to temperature dependence of anisotropy energy (K_u). The high frequency signal loss over ten-years is calculated at an in-drive temperature of 80°C for media with a thermal stability factor of 100 at room temperature. When the measured temperature dependence of the thermal stability factor is taken into account, an additional 30% decrease in the high frequency signal after ten years will be observed over that calculated using only the thermal energy k_BT. This study emphasizes the importance of under-layer and the magnetic layer in affecting temperature dependence of thermal stability factor