Analysis of Bit-shift Characteristics of Doubled-layer for Perpendicular Magnetic Recording : The Influences of Soft-under-layer on Bit-shift Characteristics

Abstract

The properties of the magnetic domains that appear in an under-layer of a double-layered medium during recording process are investigated using computer simulation. Further, their influences on recording properties are discussed. The magnetic domains are in a thermodynamically non-equilibrium state. They appear instantaneously in recording process, and they vanish immediately with the removal of recording head by thermal agitation. But the additional fields generated from the wall charges affect considerably on the bit-shift characteristics, which results in the increase of jitter noise.