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A micromagnetic simulation is conducted to study the write field dynamics in the presence of antiferromagnetic exchange coupling (AFC) of writer pole for a perpendicular magnetic recording (PMR) writer head. It is found that, depending on the actual configuration of the AFC coupling in the yoke and the pole tip, there could be an intermediate transient state near zero write field during the magnetization reversal, compared to the normal writer design without AFC coupling. This transient state may cause recording performance degradation. We further investigated the AFC coupling effect on the remanent field in the degauss process. For different performance aspects, i.e., field dynamics, maximum field, and remanent field, the AFC in the yoke and in the pole tip plays different roles. [ABSTRACT FROM AUTHOR]

In this paper, finite element method (FEM) solving Maxwell's equations is used to study writer head design with side shields. A half side shielded writer is investigated due to the belief that writer designs with larger side fringing field can be accommodated in shingled recording. It was found that although a half side shielded writer provides higher on track field, curvature at track edge is also increased. The increasing curvature poses a limit on the writer pole width increment. Designing a writer to maintain low curvature while obtaining high on-track field continues to be the challenge for shingled recording. This paper explores a full range of writer design parameters using finite element modeling and introduces several design features for a wrap-around shielded writer. [ABSTRACT FROM PUBLISHER]

The characteristics of spatial and temporal field distributions are presented for wrap-around-shielded perpendicular magnetic recording writers. Micromagnetic modeling simulations are conducted to study the effects of shield thickness and the magnetization on the shield-related side field. An improvement of side field is found with the thicker shield thickness and higher saturation magnetization. The maximum side field is spatially and time dependent during the dynamic writing process. The side field reaches the maximum around the transitions, where the write field from the main pole is at the minimum. In addition, the write current rise-time effect on the side field is investigated. [ABSTRACT FROM PUBLISHER]

This paper presents a study of the degauss process of a perpendicular magnetic writer pole using micromagnetic modeling as a tool. The dynamics of the yoke and the pole-tip magnetization relaxation during degauss are studied in detail, and the remanent field of the pole tip is used as a metric to measure the effectiveness of each of the degauss methods. Various aspects of the degauss current waveforms are investigated, such as frequency, duration, initial current amplitude, amplitude decay envelope, and overshoot. Some alternative waveforms, i.e., unipolar reverse pulse degaussing, have also been examined. It has been found for many of the parameters to have an optimal range outside of which the degauss effectiveness and efficiency are degraded. [ABSTRACT FROM AUTHOR]

We present a systematic study of write field asymmetry by using micromagnetic modeling for a perpendicular magnetic recording (PMR) writer structure. Parameters investigated include initial magnetization condition, write current amplitude, write current frequency, and initial write current polarity. It is found that the write current amplitude and frequency (data rate) are the dominant factors that impact the field asymmetry. Lower write current amplitude and higher write current frequency will deteriorate the write field asymmetry, causing recording performance (such as bit error rate) degradation. [ABSTRACT FROM AUTHOR]