磁気超解像再生層の磁区構造

抄録

The stripe domain structure in a readout layer with a small perpendicular anisotropy in CAD media was calculated on the basis of three proposed stripe domain models. Without a magnetic field, the triangular-cross-section stripe domain appears only in the narrow range of Q=K_u/(2πM_s²), but when a leakage field of 100 Oe is applied from the memory layer, it becomes stable for a wide range of Q values below a critical value. For Q values above a critical value, the trapezoidal-cross-section stripe domain is stable. The distribution of the stable domain structure in the readout light spot was calculated, using the temperature profile and temperature dependence of magnetic parameters, on the basis of molecular field theory. The results show that a single domain in the perpendicular direction is stable in the spot’s center for a leakage field of 100 Oe, and that triangular stripe domain area is expanded in the spot’s circumference for a leakage field of 200 Oe. The result is discussed in relation to the copying process and the gray masking phenomenon.