Nano-Contact Magnetic Random Access Memory Devices

提出了一种基于纳米接触弹道磁阻和电流感应磁化开关的新型全金属磁随机存取存储器件的研究和教育倡议。计划的研究目标如下：-了解支配磁性纳米收缩上的电传输的机制-了解使用高速电流脉冲的磁场壁传播的机制-基于这些用于检测和记录的新概念设计和制造磁随机存取存储器的原型。在本项目中，我们为磁性随机存取存储器件(MRAM)提供了一种完全不同的工作原理。我们没有利用多层器件中的巨磁电阻进行回读，而是提出了一种与通常的MRAM中的传统方法根本不同的方案，即依靠外部电流来产生高于铁磁层矫顽力的磁场。在这种方法中，我们将利用所谓的“S-d交换”相互作用来移动磁区墙。其原理是使用脉冲电流沿电子速度方向移动畴壁。教育努力包括对专门研究磁学的研究生和本科生进行培训，以及开发一种以网络为基础的教学工具，直观地演示磁性行为的一些关键方面。该项目将根据实际实验结果制作磁性现象的动画视频，并将通过互联网以电子方式传播给广大观众。目标是增进对磁性的了解，促进对科学技术的热情。这些努力将利用表面科学、纳米光刻、扫描探针显微镜、磁性成像和设备制造方面的现有技术专长和实验能力。这个项目借鉴了美国国家科学基金会职业奖的结果，代表了一个相关但独特的研究方向。

A research and educational initiative to develop a new all-metal magnetic random access memory device, based on nano-contact ballistic magnetoresistance and current-induced magnetization switching is proposed. The following research goals are planned:- To understand the mechanisms that govern the electrical transport on magnetic nanoconstrictions- To understand the mechanisms for domain wall propagation usinghigh-speed current pulses - To design and fabricate a prototype magnetic random accessmemory based on these new concepts for detection and recording. In this project, we offer a completely different operating principle for magnetic random access memory devices (MRAMS). Instead of exploiting giant magnetoresistance in multilayer devices for readback, we propose a scheme which is fundamentally different from the conventional approach in usual MRAM'S, which rely on external currents to produce magnetic fields higher than the coercivity of the ferromagnetic layers. In thismethod, we will utilize the so called "s-d exchange" interaction to move domain walls. The principle is to use pulsed current to move domain walls in the direction of electron velocity. The educational efforts include the training of graduate and undergraduate students specializingin magnetism, and the development of a web-based teaching tool that visually demonstrates some of the key aspects of magnetic behavior. This project will produce animation videos of magnetic phenomena derived from actual experimental results and will be disseminated electronically via the internet to reach a broad audience. The goal is to enhance the understanding of magnetism and promote enthusiasm towards science and technology. These efforts will utilize the existing technical expertise and experimental capabilities in surface science, nanolithography, scanned probe microscopy, magnetic imaging, and device fabrication. Thisproject is leveraged upon the results of an NSF CAREER award, and represents a related but distinct research direction.