Micromagnetic modeling of head field rise time for high data-rate recording
Micromagnetic modeling of head field rise time for high data-rate recording
复制标题
高数据速率记录的磁头场上升时间的微磁建模
DOI：
10.1109/tmag.2004.839071
复制
发表时间：
2005
影响因子：
2.1
通讯作者：
S. Batra
中科院分区：
文献类型：
--
作者：
W. Scholz;S. Batra
我们已经开发了一个有限元微磁学模型，以调查在高密度和高数据速率的垂直记录写头的动力学。该模型包括整个头部几何形状，以及大返回极和软底层。磁头对线圈电流的响应取决于电流波形和持续时间、吉尔伯特阻尼常数以及软底层和屏蔽的存在。大阻尼导致线圈电流和磁头磁场之间的大相移，而小阻尼导致强旋磁进动。我们发现，阻尼常数的中间值给出了最快的头场上升时间。通过将线圈匝数从两圈减少到一圈并缩短磁轭长度，本征反转时间从540 ps减小到250 ps。因此，最大数据速率需要阻尼常数的中间值、短轭长度和快速电流上升时间。
We have developed a finite-element micromagnetics model to investigate the dynamics of write heads for perpendicular recording at high density and high data-rates. The model includes the entire head geometry, with the large return pole and the soft underlayer. The response of the head to the coil current is determined by the current waveform shape and duration, Gilbert damping constant, and presence of soft underlayer and shields. Large damping leads to a large phase shift between the coil current and the head field while small damping causes strong gyromagnetic precession. We find that an intermediate value of the damping constant gives the fastest head field rise time. The intrinsic reversal time decreases from 540 to 250 ps by reducing coil-turns from two to one and shortening the yoke length. Thus, an intermediate value of the damping constant, short yoke length, and fast current rise time are needed for maximum data rate.