Faster magnetic walls in rough wires
Faster magnetic walls in rough wires
复制标题
DOI：
10.1038/nmat931
复制
发表时间：
2003-08-01
期刊：
影响因子：
41.2
通讯作者：
Miltat, J
中科院分区：
文献类型：
--
作者：
Nakatani, Y;Thiaville, A;Miltat, J
在已经提出的一些磁器件中，信息通过畴壁（DW）运动沿亚微米宽度的磁线沿着传输。该装置的速度显然与DW速度有关，在中等磁场中的测量值高达1 km s-1。虽然在具有高各向异性的正铁氧体晶体薄膜中已经达到了这样的速度，但令人惊讶的是，它们在低各向异性坡莫合金中的观察结果。我们已经研究了，通过数值模拟，DW在这样的样品中的传播，并观察到一个非常违反直觉的行为。对于完美的样品（没有边缘粗糙度），计算出的速度随着场的增加而增加到阈值，超过阈值它会突然下降-这是一个众所周知的现象。然而，对于粗糙的带材边缘，速度击穿被发现被抑制。我们解释了这一现象，并建议粗糙度，而不是避免制造纳米结构DW传播时，应设计。
In some magnetic devices that have been proposed, the information is transmitted along a magnetic wire of submicrometre width by domain wall (DW) motion,. The speed of the device is obviously linked to the DW velocity, and measured values up to 1 km s−1have been reported in moderate fields. Although such velocities were already reached in orthoferrite crystal films with a high anisotropy, the surprise came from their observation in the low-anisotropy permalloy. We have studied, by numerical simulation, the DW propagation in such samples, and observed a very counter-intuitive behaviour. For perfect samples (no edge roughness), the calculated velocity increased with field up to a threshold, beyond which it abruptly decreased — a well-known phenomenon. However, for rough strip edges, the velocity breakdown was found to be suppressed. We explain this phenomenon, and propose that roughness should rather be engineered than avoided when fabricating nanostructures for DW propagation.