Simulation of thermal stability of a keepered medium with a soft magnetic underlayer

Two-dimensional finite element numerical read/write simulation at finite te mperatures was performed on a keepered medium (KM) with a soft magnetic und erlayer and a thin-film head system. The M-H model for the recording layer is a so-called Stoner-Wohlfarth model modified by taking account of a therm al switching of each particle using a Monte Carlo method. The output voltag e reductions at 300 K due to the thermal fluctuation for the KM with the re cording layer of M-r = 680 kA/m, t = 36 nm and H-c = 159 kA/m, KuV/k(B)T = 30 and 50 and with the optimized keeper layer were calculated to be 9.7% fo r KuV/k(B)T = 30 and 3.2% for KuV/k(B)T = 50, though those for the media wi thout the keeper layer were 20.4% and 12.5%, respectively. In conclusion, t he KM may be a hopeful candidate for improving the thermal stability in a h igh density magnetic recording.