The effects of thermal-induced transition decay and broadening on magnetic recording performance

The relationship between media noise reduction and thermal stability is explored. It is shown that the "magnetic" grain size that effects the media noise and the switching volume of the media are strongly related. Additionally, the effect of temperature on coercivity is investigated over the range of temperatures over which disk drives typically operate. From this, the effect of temperature on media anisotropy can be deduced. It is shown that alloy composition can have an effect on this dependence. The pattern-dependence of thermal decay of recorded data is investigated using constant frequency and di-bit patterns. It is found that a constant frequency pattern decays faster than a di-bit pattern with the same intertransition spacing and it is suggested that the decay rates of these two patterns provide an upper and lower limit for thermal decay at a particular transition spacing.