Magnetoresistive sensors for magnetic domain wall technologies

用于磁畴壁技术的磁阻传感器

• 批准号: EP/F069359/1
• 负责人: Daniel Allwood
• 金额: $ 61.22万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FF069359%2F1
• 关键词: Magnetoresistive; sensors; magnetic; domain; wall

Recent developments in magnetic nanotechnology have seen new device concepts emerge that could challenge traditional silicon-based microelectronics in certain applications. A key advantage of magnetic devices over alternative technologies is that they generally do not require power to retain data. In specific cases, magnetic nanotechnology devices may also offer higher device density, lower power consumption, improved reliability or additional functionality compared with their rivals. Some of these magnetic devices are made using thin ferromagnetic layers separated by a non-magnetic metal spacer layer just a few atoms thick. The upper and lower layer will have different magnetisation directions and the electrical resistance of the overall device depends on their relative orientation due to an effect known as 'giant magnetoresistance' (GMR). Already, these devices are widely used as magnetic field sensors in many applications, e.g. in computers and automotive products. Other technologies are being developed based upon networks of planar magnetic nanowires, usually with just a single magnetic layer and no spacer layers. The geometry of the wires is important, since this restricts magnetisation to lie in one of two directions along the wire axis. This provides a simple system for representing the binary numbers of digital information. Opposite magnetisation directions can meet, and where this happens, they are separated by a transition region known as a 'domain wall'. Domain walls can be easily created or removed and made to propagate through a nanowire network using magnetic fields or electrical currents in the nanowires. In this way, information is written, deleted and sent through a circuit, be it a sensor, memory or logic device. However, for these devices to be commercially successful, we must have read-out of the magnetic data in form compatible with modern electronics. There have not been any demonstrations of this to date. In this collaborative research programme, we will address this deficiency by developing a nanoscale device to read data in magnetic nanowires. Our recent calculations have shown that the magnetic field from domain walls is very high close to the nanowires. We will use this field to change the magnetic configuration of a nearby sensor and detect these changes using GMR. This will be a significant step for magnetic nanowire technologies since it will allow nanowire devices to be fully integrated as stand-alone integrated circuits. We will also use these sensors for scientific measurements to improve our understanding of the behaviour of domain walls in magnetic nanowires.The applicants for this project bring together world-leading experience in nanofabrication, magnetic nanowires, GMR materials and computer modelling of nanoscale magnetic systems, making this the ideal team to undertake such a challenging project.

磁纳米技术的最新发展已经看到了新的器件概念的出现，可能会在某些应用中挑战传统的硅基微电子技术。磁性设备相对于替代技术的一个关键优势是，它们通常不需要电力来保存数据。在特定情况下，与竞争对手相比，磁性纳米技术设备还可以提供更高的设备密度，更低的功耗，更高的可靠性或额外的功能。这些磁性器件中的一些是使用薄铁磁层制成的，该铁磁层由仅几个原子厚的非磁性金属间隔层隔开。上层和下层将具有不同的磁化方向，并且由于一种称为“巨磁电阻”（GMR）的效应，整个器件的电阻取决于它们的相对方向。这些器件已经在许多应用中广泛用作磁场传感器，例如在计算机和汽车产品中。其他技术正在开发基于平面磁性纳米线的网络，通常只有一个单一的磁性层，没有间隔层。线的几何形状是重要的，因为这限制磁化位于沿沿着线轴的两个方向之一。这提供了一个简单的系统来表示数字信息的二进制数。相反的磁化方向可以相遇，并且在这种情况下，它们被称为“畴壁”的过渡区域分开。域壁可以很容易地产生或去除，并使用纳米线中的磁场或电流传播通过纳米线网络。通过这种方式，信息被写入，删除和通过电路发送，无论是传感器，存储器还是逻辑器件。然而，为了使这些设备在商业上取得成功，我们必须以与现代电子学兼容的形式读出磁性数据。迄今为止，还没有任何这方面的示范。在这项合作研究计划中，我们将通过开发一种纳米级设备来读取磁性纳米线中的数据来解决这一缺陷。我们最近的计算表明，来自畴壁的磁场在纳米线附近非常高。我们将利用这个磁场来改变附近传感器的磁结构，并利用GMR检测这些变化。这将是磁性纳米线技术的重要一步，因为它将允许纳米线器件完全集成为独立的集成电路。我们也将利用这些传感器进行科学测量，以提高我们对磁性纳米线中畴壁行为的理解。该项目的申请人汇集了在纳米纤维、磁性纳米线、GMR材料和纳米磁性系统计算机建模方面的世界领先经验，使其成为承担这样一个具有挑战性项目的理想团队。

项目成果

Head and bit patterned media optimization at areal densities of 2.5Tbit/in2 and beyond

面密度为 2.5Tbit/in2 及以上的头和位图案介质优化

• DOI: 10.1016/j.jmmm.2010.11.081
• 发表时间: 2012
• 期刊: Journal of Magnetism and Magnetic Materials
• 影响因子: 2.7
• 作者: Bashir M

The incorporation of the Cauchy stress matrix tensor in micromagnetic simulations

• DOI: 10.1063/1.3489969
• 发表时间: 2010-10
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: J. Dean;M. Bryan;G. Hrkac;A. Goncharov;C. Freeman;M. A. Bashir;T. Schrefl;D. Allwood

Stress-based control of magnetic nanowire domain walls in artificial multiferroic systems

• DOI: 10.1063/1.3532041
• 发表时间: 2011-01-15
• 期刊: JOURNAL OF APPLIED PHYSICS
• 影响因子: 3.2
• 作者: Dean, J.;Bryan, M. T.;Allwood, D. A.
• 通讯作者: Allwood, D. A.