Superfluid-inspired reconfigurable magnetic devices

处理和传输信息是当今信息时代的中心任务。执行此任务的当前设备需要增加的功率量。另一方面，诸如移动的计算之类的许多现代应用不能访问大电源以保持功能。这就需要寻找处理和传输信息的替代手段。超流性，即信息在没有耗散的情况下的连贯流动，为这个问题提供了理想的解决方案。然而，在迄今为止探索的材料中，超流性仅限于低温。最近，利用磁性材料的有效电和热激发的进步，已经提出在室温磁性材料中存在超流性激发的现象。该项目的目标是利用这种超流启发的现象，提出和数值评估节能超流启发的磁性装置。特别是，首席研究员将构建约瑟夫森结的新型磁性类似物，这是传统低温信息处理和通信设备的基石。此外，利用磁性材料具有固有的长记忆和可调特性的事实，还将探索超出传统约瑟夫森结的器件功能。在这个项目中，首席研究员将培训本科生和研究生，在现代材料建模，以提高美国？科学，技术，工程和数学的劳动力。拟议的研究旨在揭示新的超流体启发的磁性设备，涵盖方面-从使用新的磁性材料开始，以设计和基准测试的应用驱动的设备概念。为此，将努力实现以下具体目标：（a）受超导约瑟夫森的启发，设计新颖的基于磁绝缘体的约瑟夫森结，（B）发展用于电和热偏置驱动的自旋通过磁约瑟夫森结的超流的电路理论（与超导约瑟夫森结非常相似）利用自旋轨道和热磁力矩的现象，以及（c）使用电路理论来组装磁性约瑟夫森结，以用于构造新类别的磁性装置，并将其基准化用于经典到量子信息处理、通信和能量收集应用。最后一个目标利用了基于超导约瑟夫森结的成熟器件概念，该概念可以在我们提出的磁绝缘系统中模仿。此外，所提出的磁性装置（是电可重新配置的和非易失性的）添加了超出基于超导体的装置中存在的那些功能的功能，诸如对超出冯-诺依曼存储器内计算架构的可适应性。探索这种装置的概念也将构成最后一个目标的一个组成部分。所提出的方法相结合，第一次，超流体为基础的约瑟夫森现象与上述室温有序的磁铁。通过利用磁体的超流体性质，它开辟了全新的途径来解决下一代信息处理和通信设备在高工作温度下实现最小能量浪费的核心技术挑战。在基本层面上，理论项目将作为一个独特的游乐场，测试和发现新的现象在磁性，超导性和热电子学的接口。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Processing and transporting information are the central tasks in today's age of information. Current devices that perform this task require increasing amount of power. Many modern applications, such as mobile computing, on the other hand, does not have access to large power sources to remain functional. This has created a need to search for alternate means to process and transport information. Superfluidity, that is coherent flow of information in the absence of dissipation, provides an ideal solution to this problem. However, in materials explored so far, the superfluidity has been limited to cryogenic temperatures. Recently, taking advantage of the advancement of efficient electrical and thermal excitation of magnetic materials, phenomena inspired from superfluidity have been proposed to exist in room temperature magnetic materials. The goal of this project is to utilize such superfluid-inspired phenomena to propose and numerically evaluate energy-efficient superfluid-inspired magnetic devices. In particular, the prinicipal investigator will construct novel magnetic analogues of Josephson junctions, which are the building blocks of conventional cryogenic information processing and communication devices. Moreover, exploiting the fact that magnetic materials have inherently long memory and tunable properties, device functionality beyond those possible in conventional Josephson junctions will also be explored. During this project, the principal investigator will train undergraduate and graduate students, in modern materials modelling, for enhancing the United States? science, technology, engineering and math workforce.The proposed research aims at unraveling novel superfluid-inspired magnetic devices by covering aspects-starting from the use of new magnetic materials to designing and benchmarking of application-driven device concepts. For this purpose, the following specific objectives will be pursued: (a) designing novel magnetic insulator-based Josephson junctions which are inspired from superconducting Josephson, (b) developing circuit theory for electrical and thermal bias driven superflow of spin through magnetic Josephson junctions (in close analogy to superconducting Josephson junctions) utilizing the phenomena of spin-orbit and thermomagnonic torques, and (c) using the circuit theory to assemble magnetic Josephson junctions for constructing new class of magnetic devices and benchmarking them for classical to quantum information processing, communication and energy harvesting applications. The last objective takes advantage of the well-developed device concepts based on superconducting Josephson Junctions, which can be mimicked within our proposed magnetic insulating systems. In addition, the proposed magnetic devices (being electrically reconfigurable and nonvolatile) add functionality beyond those existing in superconductor-based devices, such as amenability to beyond von-Neumann in-memory computing architectures. Exploring such device concepts will also form an integral part of the last objective. The proposed approach combines, for the first time, superfluid-based Josephson phenomena with above room temperature ordering of magnets. By tapping into superfluid-like properties of magnets, it opens up completely new avenues to solve the central technical challenge of achieving minimal energy wastage at high operating temperature for the next-generation information processing and communication devices. On a fundamental level, the theoretical program will serve as a unique playground to test and discover new phenomena at the interface of magnetism, superconductivity and caloritronics.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.