Energy efficient spin-torque devices

节能自旋扭矩装置

• 批准号: 2230124
• 负责人: Weigang Wang
• 金额: $ 45万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2230124&HistoricalAwards=false
• 关键词: Energy; efficient; spin; torque; devices

In most electronic devices, only the charge of electrons is utilized while another feature spin has unexplored advantages. The spin of electrons is a quantum-mechanical property that offer advantages to achieve future generations of electronics that can operate faster while consuming less energy. To date, most activities in spintronics have largely been focused on ferromagnetic materials where all the spins are aligned in the same direction and is relatively easy to read, write and store information with high fidelity. Currently, it is believed that the manipulation of spin can be even faster and potentially more energy efficient in another class of material called ferrimagnets, where the spins of different atoms point in opposite directions. In this project, the PIs proposes to investigate ferrimagnets-based devices and explore new methods to read and write information. Novel device structures, and theoretical models will be developed. The results of this research will potentially impact a wide range of applications in memory, logic, data storage, neuromorphic computing, and radiofrequency devices. In addition, the project will provide valuable training opportunities for graduate and undergraduate students, specifically from underrepresented and minority groups. In addition, the PIs will actively participate in direct outreach to the public in local or national events.In recent years, ferrimagnets have gained a great deal of attention due to their unique properties. The staggered moments in fully compensated ferrimagnets result in a zero net magnetization, which allows spin currents to penetrate much deeper, a potentially very useful feature in increasing the efficiency of spin-torque switching. Intriguing physics also exists at the angular momentum compensation points of ferrimagnets, where a finite magnetization and nonzero spin polarization persist, enabling the exploration of antiferromagnetic-like fast dynamics in ferrimagnets. In this project, the PIs will carry out a joint experimental-theoretical investigation on devices based on ferrimagnets, specifically, on spin-transfer torque and spin-orbit torque effects where the magnetization can be switched by an electric current. The PIs will develop novel devices where the ferrimagnets will be actively participating in the magnetoresistance and spin angular moment transfer process, instead of only passively providing perpendicular magnetic anisotropy to the system. Both two-terminal and three-terminal devices will be investigated, to understand the spin-transfer torque and spin-orbit torque effects, respectively. The research will be focused on the interaction of spin-polarized tunneling current with the two sublattices of ferrimagnets, to understand the roles of different spin torques (damping-like vs field-like) and to realize possible anti ferromagnetic-like dynamics in switching experiments down to 100ps.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.

在大多数电子器件中，只有电子的电荷被利用，而另一个特征自旋具有未开发的优点。电子的自旋是一种量子力学性质，它为实现未来几代电子产品提供了优势，这些电子产品可以更快地运行，同时消耗更少的能量。 迄今为止，自旋电子学的大多数活动主要集中在铁磁材料上，其中所有自旋都在同一方向上对齐，并且相对容易以高保真度读取，写入和存储信息。 目前，人们认为，在另一类称为亚铁磁体的材料中，自旋的操纵可以更快，并且可能更节能，其中不同原子的自旋指向相反的方向。 在这个项目中，PI建议研究基于亚铁磁体的设备，并探索读取和写入信息的新方法。新的器件结构和理论模型将被开发。这项研究的结果将潜在地影响存储器、逻辑、数据存储、神经形态计算和射频设备中的广泛应用。此外，该项目将为研究生和本科生，特别是代表性不足和少数群体的学生提供宝贵的培训机会。此外，PI将积极参与当地或全国性活动中的直接外联活动。近年来，亚铁磁体因其独特的性能而获得了极大的关注。在完全补偿的亚铁磁体中的交错矩导致零净磁化，这允许自旋电流穿透得更深，这是增加自旋扭矩切换效率的潜在非常有用的特征。有趣的物理学也存在于亚铁磁体的角动量补偿点，在那里有限的磁化和非零自旋极化持续存在，使亚铁磁体中类似反铁磁的快速动力学的探索成为可能。 在该项目中，PI将对基于亚铁磁体的设备进行联合实验-理论研究，特别是对自旋转移扭矩和自旋轨道扭矩效应，其中磁化可以通过电流切换。PI将开发新型器件，其中亚铁磁体将积极参与磁阻和自旋角动量转移过程，而不是仅被动地为系统提供垂直磁各向异性。两个终端和三终端设备将被调查，以了解自旋转移力矩和自旋轨道力矩的影响，分别。研究的重点是自旋极化隧穿电流与亚铁磁体的两个亚晶格的相互作用，来理解不同自旋力矩的作用（类阻尼与类场），并实现可能的反铁磁-该奖项反映了NSF的法定使命，并被认为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。