ECCS-EPSRC: Collaborative Research: Acoustically induced Ferromagnetic Resonance (FMR) assisted Energy Efficient Spin Torque memory devices

ECCS-EPSRC：合作研究：声感应铁磁谐振 (FMR) 辅助节能自旋转矩存储器件

• 批准号: 2152528
• 负责人: Caroline Ross
• 金额: $ 25万
• 依托单位: Massachusetts Institute of Technology
• 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: 2022-10-01 至 2025-09-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2152528&HistoricalAwards=false
• 关键词: ECCS; EPSRC; Collaborative; Research; Acoustically

Magnetic Random-Access Memory (MRAM) based on nanoscale magnets can retain information when power is turned off; such non-volatile memory cannot be implemented with Complementary Metal Oxide Silicon (CMOS) technology alone. However, the energy and current required to switch a state-of-the-art MRAM device is large, which limits their use to niche applications. Strain and acoustic waves can be used to significantly lower the current required to write information in such devices, but unfortunately which lacks energy density making them ineffective for nanoscale magnets scaled to very small lateral dimensions (well below 100 nanometers). The key innovation proposed in this project is to use surface acoustic waves (SAW) induced ferromagnetic resonance (FMR), a phenomenon by which energy applied to the nanomagnets is accumulated over tens of cycles to produce a large magnetization deflection in a few nanoseconds to significantly lower the current needed to switch the magnetic state of extremely small nanomagnets. This research could lead to dense, energy efficient, and non-volatile magnetic memory. The Virginia Commonwealth University (VCU) and Massachusetts institute of Technology (MIT) PIs will work with industry to transfer relevant research developments, incorporate magnetic memory modules in graduate or undergraduate classes, hold nanomagnetism workshops for high school students and engage in outreach to under-represented K-12 students through workshops and/or hosting them as summer research interns. The project work will consist of complementary materials growth and characterization (MIT), nanofabrication (MIT and VCU), device characterization (VCU), advanced time-resolved magnetization visualization (Univ. of Exeter, UK), modeling and simulation (VCU). The tasks include: (i) Growth and patterning of nanoscale magnets and deposition of interdigitated transducers (IDT) to generate SAW on piezoelectric Lithium Niobate films. (ii) Characterization of magnetization reversal in the above nanostructures with magnetic force microscopy (MFM) to find optimum SAW and spin current conditions. Samples thus identified will be sent to Exeter Univ. for study of detailed time resolved magnetization dynamics with time resolved scanning Kerr microscopy (TRSKM) under (a) SAW induced FMR (b) spin torque and (c) combination of both “a” and “b”. (iii) Performing micromagnetic modeling of the magnetization dynamics to explain the TRSKM studies and understand the dynamic error in the presence of realistic thermal noise, defects, edge roughness, etc. under combination of SAW induced FMR and SOT/STT. This closely coordinated research project would advance knowledge of rich non-linear magnetization dynamics under SAW induced FMR, spin torque and a combination of both as well as provide a proof-of-concept demonstration of this energy efficient and scalable non-volatile memory concept.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.

关闭功率时，基于纳米级磁体的磁随机记忆（MRAM）可以保留信息；仅凭完全金属氧化物硅（CMOS）技术，不能实现这种非易失性记忆。但是，切换最先进的MRAM设备所需的能量和电流很大，这限制了它们用于利基应用程序。应变和声波可用于显着降低在此类设备中写入信息所需的电流，但不幸的是，它缺乏能量密度，使得它们对于缩放到很小的横向尺寸（远低于100纳米）的纳米级磁体无效。 The key innovation proposed in this project is to use surface acoustic waves (SAW) induced ferromagnetic resonance (FMR), a phenomenon by which energy applied to the nanomagnets is accelerated over tens of cycles to produce a large magnetization deflection in a few nanoseconds to significantly lower the current needed to switch the magnetic state of extremely small nanomagnets.这项研究可能导致致密，节能和非挥发性磁记忆。弗吉尼亚州联邦大学（VCU）和马萨诸塞州技术研究所（MIT）PIS将与行业合作转移相关的研究发展，在研究生或本科课程中纳入磁性记忆模块，为高中生举办纳米磁性研讨会，并通过工作不足的K-12学生与他们一起进行工作和/或与他们一起进行，并与他们一起进行临床研究，并与他们一起进行了工作和/或与他们一起进行，并与他们一起进行了研究和//或与他们一起进行，并与他们一起进行了服务。项目工作将包括完整的材料生长和特征（MIT），纳米制作（MIT和VCU），设备表征（VCU），高级时间分辨的磁化可视化（英国埃克塞特大学），建模和仿真（VCU）。这些任务包括：（i）纳米级磁铁的生长和模式以及在压电硅甲甲甲甲膜上生成锯的插入式换能器（IDT）的沉积。 （ii）用磁力显微镜（MFM）在上述纳米结构中表征磁化反转，以找到最佳的锯和旋转电流条件。因此确定的样本将发送到埃克塞特大学。为了研究详细的时间解析磁化动力学，并在（a）锯下诱导的fMR（b）自旋扭矩和（c）“ a”和“ b”的组合（c）组合下，在（a）SAW诱导的fMR（b）诱导的fMR（b）下扫描KERR显微镜（TRSKM）。 （iii）对磁化动力学进行微磁建模来解释TRSKM研究并了解在现实的热噪声，缺陷，边缘粗糙度等存在下的动态误差等。 This closely coordinated research project would advance knowledge of rich non-linear magnetization dynamics under SAW induced FMR, spin torque and a combination of both as well as provide a proof-of-concept demonstration of this energy efficient and scalable non-volatile memory concept.This award reflects NSF's statutory mission and has been deemed precious of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.