Thermal longevity of nano-multilayer magnetic media

A common concern about the use of particles a few nanometers in size is their stability. This paper addresses a technique for estimating the longevity on the basis of measurements that can be made in a reasonable time. Using the recently developed Preisach-Arrhenius model, the decay rate can be quantified using the chemical potential. Measurements in Co/Pt multilayer media have shown that at room temperature the fluctuating field is 2.61 mT. Since at room temperature, the entire decay can be seen when a field near the coercivity is applied, the longevity can be estimated at other holding fields by a linear extrapolation.