Article ID: 23TR511
For 3D heat-assisted magnetic recording using a double-layer bit patterned medium with an upper recording layer of 4 nm and a lower recording layer of 3 nm, the possibility of recording and the effect of the magnetic interaction between the two layers were investigated using Landau-Lifshitz-Gilbert equation. The spacing between the upper and lower layers was changed to 3 nm and 4 nm, and the recording magnetization of the upper and lower layers was a pattern that recorded in opposite directions. As a result, when the upper layer was written, the difference in the maximum rise temperature between the optimum rise temperatures for the upper and the lower layers was about 10 to 15 K. Hence, a rise temperature where the BERs of the upper and lower layers were both within the allowable range was not obtained. When writing on the upper layer, the static magnetic field from the upper to the lower layer was added to the equivalent magnetic field due to thermal fluctuations, so the lower layer is overwritten even at a low rise temperature.
