CAREER: Understanding the Size Effects on Spin-mediated Thermal Transport in Nanostructured Quantum Magnets

职业：了解纳米结构量子磁体中自旋介导的热传输的尺寸效应

• 批准号: 2144328
• 负责人: Xi Chen
• 金额: $ 56.55万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2027-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2144328&HistoricalAwards=false
• 关键词: CAREER; Understanding; Size; Effects; Spin

Magnetic heat conduction, a highly efficient mode of heat conduction in some magnetic materials with unique crystal structures, is promising for thermal management, energy conversion, and emerging quantum technologies. However, experimentally probing the microscopic heat transport processes in these materials has been challenging. The overarching goals of this project are to develop a fundamental understanding of the heat transport mechanisms in magnetic materials and to educate the next generation of scientists in quantum science. Using a combination of advanced nanomaterial synthesis and nanoscale thermal characterization, this project seeks to reveal important length scales of magnetic heat conduction. The knowledge gained will potentially enable the development of magnetic materials as effective heat transport channels for thermal management in microelectronic devices, as well as a data-bus for quantum science-based devices. The integrated education plan will promote the participation of underrepresented minorities in STEM disciplines and inspire students—K-12 to graduate level—to pursue careers in science and engineering.To shed light on the mechanisms that govern the thermal transport of spin excitations (i.e., thermal excitations of electrons’ spin structure), this project effectively combines controlled bottom-up synthesis of magnetic nanostructures, advanced nanoscale four-probe thermal transport characterization, and theoretical analysis. By investigating the thermal transport properties in nanostructured quantum magnets, the proposed research will verify the predicted ballistic thermal transport of spin excitations, which can lead to a divergently increasing thermal conductivity with the system’s length. Furthermore, the effect of lateral size confinement on spin-mediated thermal transport will be established experimentally. This project will generate fundamental knowledge about energy transport in quantum materials at the nanoscale, as well as train and inspire the next generation of STEM workforce. The scientific findings from this project will impact a wide variety of applications that require transport of spin excitations, including thermal management, thermal energy conversion, and quantum information processing.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.

磁性导热是一些具有独特晶体结构的磁性材料中的一种高效导热方式，在热管理、能量转换和新兴量子技术方面具有广阔的应用前景。然而，在实验上探索这些材料中的微观热传输过程一直是具有挑战性的。这个项目的主要目标是对磁性材料中的热传输机制有一个基本的了解，并在量子科学方面教育下一代科学家。利用先进的纳米材料合成和纳米尺度的热表征相结合，该项目试图揭示磁性热传导的重要长度尺度。所获得的知识将有可能使磁性材料成为微电子设备热管理的有效热传输通道，以及基于量子科学的设备的数据总线。综合教育计划将促进未被充分代表的少数群体参与STEM学科，并激励K-12到研究生水平的学生追求科学和工程方面的职业生涯。为了阐明控制自旋激发热传输(即电子自旋结构的热激发)的机制，该项目有效地结合了自下而上受控的磁性纳米结构合成、先进的纳米级四探针热传输表征和理论分析。通过研究纳米结构量子磁体的热输运特性，这项拟议的研究将验证自旋激发的弹道热输运预测，这可能导致导热系数随系统长度的不同而增加。此外，横向尺寸限制对自旋介导的热输运的影响将在实验上建立。该项目将在纳米尺度上产生关于量子材料中能量传输的基本知识，并培训和激励下一代STEM劳动力。该项目的科学发现将影响需要传输自旋激发的广泛应用，包括热管理、热能转换和量子信息处理。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Thermal characterization for quantum materials

• DOI: 10.1063/5.0124441
• 发表时间: 2023-03
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: S. Guo;Y. Xu;Thomas Hoke;Gobind Sohi;Shuchen Li;Xiangshan Chen

Single crystal growth and thermoelectric properties of Nowotny chimney-ladder compound Fe2Ge3

• DOI: 10.1103/physrevmaterials.7.125404
• 发表时间: 2023-12
• 期刊: Physical Review Materials
• 影响因子: 3.4
• 作者: Y. Xu;Yan Wu;Huibo Cao;S. Guo;Jiaqiang Yan;Xi Chen