FET: Small: Magnonic Active Ring Memory and Logic

由于大数据技术、物联网（IoT）和生物信息学的快速发展，现代数据中心的规模呈指数级增长。 磁存储技术已被证明是云计算和大数据存储的核心平台。 所有的磁存储设备可以分为顺序存取存储器或随机存取存储器。 例如，为了读出磁带中的一位，磁带应该被缠绕，并且阅读头被放置成与所需位接触（顺序存取）。相比之下，磁阻随机存取存储器（MRAM）中的任何位可以在任何给定时间立即被访问。 无论存取过程如何，现有的磁性存储器设备，包括磁带、硬盘驱动器和MRAM，都继承了一个基本的限制：它们基于磁阻效应，这限制了一次可以读出的位数。反过来，这对大型磁数据库搜索施加了时间限制。这个问题已经刺激了对用于磁位读出的替代方法的研究（例如，多头多磁道磁存储器）。总的来说，非常需要一种用于并行磁位读出和处理的新技术。该项目还将通过将本科生、研究生和代表性不足的学生纳入该项目的机制来提高他们的教育经验，从而为急需的技术劳动力发展做出贡献。在该项目中，将开发一种新型的磁存储器，使用自旋波进行信息读出和处理。自旋波-或磁振子，自旋波的量子-代表磁有序介质中电子自旋子系统的激发，并在铁磁体和亚铁磁体以及反铁磁体中观察到。铁氧体结构中自旋波的相干长度在室温下可以大到一厘米，允许人们利用自旋波干涉。自旋波装置的操作类似于光学全息装置，其使用相干光束进行信息检索。自旋波方法的独特之处在于能够将联合收割机全息逻辑单元与磁存储器结合起来。本项目旨在探讨利用自旋波进行并行磁位读出的可行性，研究器件对结构缺陷的免疫力，并研究磁振子和电子电路的组合。这一变革性研究的成果将增加材料科学、信号处理和计算机工程领域的核心知识。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The size of modern data centers is growing exponentially due to the rapid development of Big Data techniques, Internet of Things (IoT), and Bioinformatics. Magnetic storage technology has been proven to be the core platform for cloud computing and Big Data storage. All magnetic storage devices can be classified as either sequential-access memory or random-access memory. For instance, in order to read out one bit in magnetic tape, the tape should be wound and the reading head placed in contact with the desired bit (sequential access). In contrast, any bit in magneto-resistive random-access memory (MRAM) can be accessed immediately at any given time. Regardless of the access process, the existing magnetic memory devices, including magnetic tape, hard-disk drives, and MRAM inherit one fundamental restriction: they are based on the magneto-resistance effect, which limits the number of bits which can be read out at a time. In turn, this imposes time constraints for a large magnetic database search. This problem has stimulated search for alternative methods for magnetic bit read-out (e.g., multi-head multi-track magnetic memory). Overall, there is a great need for a novel technology for parallel magnetic bit read-out and processing. The project will also enhance the educational experience of undergraduate, graduate and underrepresented students by via mechanisms for including them in the project, and thereby contributing to the much-needed technological-workforce development.In this project, a new type of magnetic memory using spin waves for information read-out and processing will be developed. Spin waves — or magnons, the quanta of spin waves — represent the excitations of the electron spin subsystem in magnetically ordered media and are observed in ferro- and ferri-magnets, as well as in anti-ferromagnets. The coherence length of spin waves in ferrite structures may be as large as one centimeter at room temperature, allowing one to exploit spin wave interference. The operation of spin-wave devices is similar to optical-holographic devices, which use coherent optical beams for information retrieval. The uniqueness of the spin-wave approach is the ability to combine holographic logic units with magnetic memory. This project aims to explore the feasibility of using spin waves for parallel magnetic bit read-out, to investigate device immunity to structure imperfections, and to study a combination of magnonic and electronic circuits. The result of this transformative research will add to the core knowledge in the area of material science, signal processing, and computer engineering.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.