CAREER: A roadmap to atomically ordered complex materials via control of entropic mixing

职业：通过控制熵混合实现原子有序复杂材料的路线图

• 批准号: 2047251
• 负责人: Adam Hauser
• 金额: $ 52.39万
• 依托单位: University of Alabama Tuscaloosa
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2047251&HistoricalAwards=false
• 关键词: CAREER; roadmap; atomically; ordered; complex

Non-Technical AbstractThe ability to atomically order crystalline materials is central to advancing technology. In the 1980s, 99% atomic ordering in two-element materials was developed, wherein two elements alternate nearly perfectly in their atomic site occupations. This enabled high-frequency transistors, which led to the cell phone revolution and high-efficiency solar panel technologies. Theoretical predictions tout revolutionary new material properties in complex (3+ elements) materials that will make possible new devices with broad application in information technology, solar cells, lighting, microwave communications, thermoelectrics, and power electronics. However, achieving the 99% atomic ordering required to realize those properties has remained elusive. The goal of this project is to systematically gain an understanding of the fundamental ordering mechanisms in complex materials. This research integrates computational theory and experimental results to create a set of criteria that can be used to design materials of sufficiently high atomic ordering (99%) to realize their intrinsic properties. This research directly integrates educational activities to impact underrepresented minorities, women, and underserved rural communities in STEM fields, and ensure that undergraduate education includes research experience. This mentor-based strategy focuses on elevating science, technology, engineering and mathematics (STEM) educators in underrepresented communities in rural Alabama and Mississippi. K-12 educators gain access to university faculty and specialists at the Alabama Science in Motion program to plan classes and laboratory sessions, and through the Alabama Math, Science and Technology Summer Institute receive training to qualify their rural school district for program/equipment funding. Undergraduate summer researchers are recruited from local Historically Black Colleges and Universities, minority-serving institutions and the American Physical Society’s Conferences for Undergraduate Women in Physics. Undergraduate students will also work as research assistants during each school year.Technical AbstractImperfect atomic ordering in complex materials is a pervasive issue in the condensed matter and materials communities: A model that accounts for entropic mixing disorder is required before complex materials can be applied widely. First principles calculations can accurately predict the intrinsic (structural, electronics, magnetic/magnetodynamic) material properties of an ordered system, but near-perfect (99%) atomic ordering is needed to manifest those properties. At present, it is a complex and computationally expensive task to determine if the system can form with the required atomic ordering in the presence of thermal and growth energies. The central hypothesis of this research is that high atomic ordering can be predicted by incorporating existing metallurgical metrics that indicate the level of entropic mixing. To test the hypothesis, computational predictions of ordering and properties are produced for a range of three-element L21-ordered Heusler alloys, chosen specifically due to decades-long frustration in realizing predictions of high spin polarization due to atomic disorder. Although applications often prefer highly ordered systems, materials with a range of ordering levels are selected to refine a robust quantitative model and provide a roadmap for material design. Thin films of each material system are grown with low energetics by the Sputter Beam Epitaxy method invented by the principal investigator, such that atomic ordering and material properties of each system can be compared to predictions with minimal extrinsic contribution. The results form a feedback loop between theory and experiment to establish and refine a quantitative model of atomic ordering when three or more elements are used. A quantitative predictive model for atomic ordering in complex alloys broadly translates to the many other fields whose material systems are plagued by entropic mixing.This project is jointly funded by the Electronic and Photonic Materials Program and the Established Program to Stimulate Competitive Research.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.

非技术摘要晶体材料的原子排序能力是先进技术的核心。在 20 世纪 80 年代，二元材料中 99% 的原子排序被开发出来，因此两种元素的原子位置几乎完美地交替，这使得高频晶体管成为可能。 ，这导致了手机革命和高效太阳能电池板技术，理论预测吹捧了复杂（3+元素）材料的革命性新材料特性，这将使在信息领域得到广泛应用的新设备成为可能。然而，实现这些特性所需的 99% 原子有序度仍然难以实现。该项目的目标是系统地了解原子有序化的基本机制。这项研究整合了计算理论和实验结果，创建了一套标准，可用于设计具有足够高原子有序度（99％）的材料，以实现其内在特性。这项研究直接整合了教育活动，以影响代表性不足的少数群体，这项以导师为基础的战略侧重于提升阿拉巴马州和密西西比州农村地区代表性不足的社区的科学、技术、工程和数学 (STEM) 教育工作者的水平。教育工作者可以通过阿拉巴马州运动科学计划与大学教师和专家联系，以计划课程和实验室课程，并通过阿拉巴马州数学、科学和技术暑期学院接受培训，以使其农村学区有资格获得项目/设备资助。都是从当地招募的历史上，黑人学院和大学、少数族裔服务机构和美国物理学会物理学本科女学生会议也将在每个学年担任研究助理。技术摘要复杂材料中的不完美原子排序是凝聚态物质中普遍存在的问题。和材料界：在广泛应用复杂材料之前，需要一个能够解释熵混合无序的模型，才能准确预测本征（结构、电子、磁/磁动力学）。有序系统的材料属性，但需要近乎完美（99％）的原子排序来体现这些属性，目前，确定系统是否可以在存在的情况下形成所需的原子排序是一项复杂且计算量大的任务。这项研究的中心假设是，可以通过结合表明熵混合水平的现有冶金指标来预测高原子有序性。三元L21 有序赫斯勒合金，是由于几十年来在实现由于原子无序导致的高自旋极化的预测方面遇到的挫折而专门选择的，尽管应用通常更喜欢高度有序的系统，但选择具有一系列有序水平的材料来完善稳健的定量模型和。为材料设计提供了路线图。每个材料系统的薄膜都是通过首席研究员发明的溅射束外延方法以低能量生长的，这样每个系统的原子排序和材料特性就可以与预测进行比较。当使用定量或更多元素时，结果形成理论和实验之间的反馈循环，以建立和完善原子排序模型。复杂合金中原子排序的定量预测模型广泛应用于其材料系统的许多其他领域。受到熵混合的困扰。该项目由电子和光子材料计划和刺激竞争性研究既定计划共同资助。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准。

项目成果

Phase and d-d hybridization control via electron count for material property control in the X2FeAl material class

通过电子计数进行相和 d-d 杂化控制，用于 X2FeAl 材料类别中的材料特性控制

• DOI: 10.1016/j.jmmm.2024.171932
• 发表时间: 2024-03-01
• 期刊: Journal of Magnetism and Magnetic Materials
• 影响因子: 2.7
• 作者: K. Law;Ridwan Nahar;Riley Nold;Michael Zengel;Justin Lewis;Adam J. Hauser
• 通讯作者: Adam J. Hauser

Dataset on density functional theory investigation of ternary Heusler alloys

三元霍斯勒合金密度泛函理论研究数据集

• DOI: 10.1016/j.dib.2023.109971
• 发表时间: 2024-02
• 期刊: Data in Brief
• 影响因子: 1.2
• 作者: Nahar, Ridwan;Law, Ka Ming;Roden, Thomas;Zengel, Michael;Lewis, Justin;Budhathoki, Sujan;Nold, Riley;Avlani, Harshil;Akintunde, Babajide;Derksen, Naomi;et al
• 通讯作者: et al

Formation of Mn-rich interfacial phases in Co2FexMn1-xSi thin films

Co2FexMn1-xSi 薄膜中富锰界面相的形成

• DOI: 10.1016/j.jmmm.2024.171884
• 发表时间: 2024-03
• 期刊: Journal of Magnetism and Magnetic Materials
• 影响因子: 2.7
• 作者: Ming Law, Ka;Thind, Arashdeep S.;Pendharkar, Mihir;Patel, Sahil J.;Phillips, Joshua J.;Palmstrom, Chris J.;Gazquez, Jaume;Borisevich, Albina;Mishra, Rohan;Hauser, Adam J.
• 通讯作者: Hauser, Adam J.

Ultralow effective Gilbert damping and induced orbital moment in strain-engineered FeGe films with Curie temperature exceeding room temperature

居里温度超过室温的应变工程 FeGe 薄膜中的超低有效吉尔伯特阻尼和诱导轨道矩

• DOI: 10.1016/j.jmmm.2022.170053
• 发表时间: 2022-12
• 期刊: Journal of Magnetism and Magnetic Materials
• 影响因子: 2.7
• 作者: Budhathoki, Sujan;Sapkota, Arjun;Law, Ka Ming;Ranjit, Smriti;Stephen, Gregory M.;Heiman, Don;Jamer, Michelle E.;Mewes, Tim;Hauser, Adam J.
• 通讯作者: Hauser, Adam J.