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| Simulation of the Effect of Soft Underlayer Domain Wall Structure on Output Signal in Perpendicular Magnetic Recording |
| Journal of Magnetics, Volume 11, Number 2, 30 Jun 2006, Pages 83-86 |
Eun-Sik Kim*  (Semiconductor Devices and Material Lab. Samsung Advanced Institute of Technology), Chee-Kheng Lim(Semiconductor Devices and Material Lab. Samsung Advanced Institute of Technology), Yong-Su Kim(Semiconductor Devices and Material Lab. Samsung Advanced Institute of Technology), Ju Lee(Dep. of electrical engineering, Hanyang University) |
| Abstract |
| Controlling magnetic domains in soft underlayer (SUL) of perpendicular magnetic recording (PMR) is an important issue for the application of PMR in HDD. We studied the magnetic domain structures in SUL using the finite element based micromagnetic simulation (FEMM) for the SUL models with different thicknesses. The purpose is to simulate the magnetic domain wall noise when the SUL thickness and saturation magnetization are changed. The simulation results show that a 15 nm SUL forms simpler Neel wall domain wall pattern and 40 nm SUL forms complex Bloch wall. To visualize the effect of these domain walls stray field at a read sensor position, the magnetic stray field of the domain walls at air bearing surface (ABS) which is 50 nm above the SUL was simulated and the results imply that Bloch walls have stronger stray field with more complicated field patterns than Neel walls and this becomes a significant noise source. Therefore, the thickness of the SUL should be controlled to avoid the formation of Bloch walls. |
| Keywords: FEMM (Finite Element Micromagnetic Model); micromagnetics; PMR (Permendicular Magnetic Recording); soft underlayer; domain wall |
| DOI: |
| Full Text: PDF |
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