MRI: Acquisition of a Cryogen-Free Physical Properties Measurement System (PPMS DynaCool)

MRI：获得无冷冻剂物理特性测量系统 (PPMS DynaCool)

• 批准号: 1828348
• 负责人: Sara Haravifard
• 金额: $ 48.86万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-10-01 至 2021-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1828348&HistoricalAwards=false
• 关键词: MRI; Acquisition; Cryogen; Free; Physical

Many of the pressing challenges that technologies are facing today in moving toward manufacturing the next generation of supercomputers or advanced communication tools can be solved with the targeted control of materials functionalities (e.g., electrical, magnetic or thermal properties). Measuring physical properties of materials under accurately controlled conditions plays a key role in understanding atomic scale properties of the new materials and accessing their utility for technical applications. The acquisition of the cryogen-free Physical Properties Measurement System (PPMS DynaCool) empowers researchers at Duke University to measure a wide range of materials properties with a high sample-throughput rate, without the need for any liquid cryogens. This state-of-the-art instrument not only enables the research training of students and postdoctoral associates, but it also benefits undergraduate and graduate engineering and science laboratory courses, and the extensive education outreach programs focused on materials research that are already in place at Duke for high school students, high school teachers, and undergraduates. This instrument is also available to the broader Research Triangle community, furthering the goal of developing a more diverse scientific workforce.----------The Physical Properties Measurement System (PPMS) is an important addition to Duke University?s materials research infrastructure and will greatly impact many areas of scientific inquiry, ranging from fundamental studies of quantum magnetism, topological effects and emergent critical phenomena, to electrical transport in nanomagnets and superconducting nanostructures, to designing and evaluating molecular, nanoscale and macroscopic materials, to studies of electronic correlations in carbon nanotubes and graphene, to characterization of novel organic semiconductor and hybrid materials for energy applications, to synthesis and characterization of high-temperature superconductors. The PPMS is equipped with an integrated conduction-cooled superconducting 14 Tesla magnet. This system provides seamless temperature transition and is capable of cooling the sample chamber from room temperature to 1.8 K and stabilizing to better than 0.001 K in under 45 minutes. A dilution refrigerator insert provides the capability to conduct measurements down to 50 mK, essential for probing quantum mechanical phenomena in materials. The sample chamber accommodates a wide range of measurement inserts, all of which allow fully automated data acquisition under computer control over the full range of magnetic field and temperature. A multi-function probe accommodates custom experiments, and a horizontal sample rotator allows magnetoresistance measurements as a function of sample orientation relative to magnetic field. This system provides the capability to measure electrical resistivity, thermal conductivity, specific heat, Hall Effect, and other thermoelectric properties, as well as susceptibility and magnetization. The cryogen-free feature of this system ensures cost-effective and reliable long-term operation of the equipment, enabling it to accommodate the large user base it will serve.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.

如今，技术在制造下一代超级计算机或先进通信工具方面面临的许多紧迫挑战可以通过对材料功能（例如电、磁或热性能）的有针对性的控制来解决。在精确控制的条件下测量材料的物理性质对于了解新材料的原子尺度性质并获得其技术应用的效用起着关键作用。购买无制冷剂物理特性测量系统 (PPMS DynaCool) 使杜克大学的研究人员能够以高样品吞吐量测量各种材料特性，而无需任何液体制冷剂。这种最先进的仪器不仅能够对学生和博士后进行研究培训，而且还有益于本科生和研究生的工程和科学实验室课程，以及已经实施的以材料研究为重点的广泛教育推广计划。杜克大学适合高中生、高中教师和本科生。该仪器还可供更广泛的研究三角社区使用，进一步实现了培养更加多元化的科学队伍的目标。------------物理特性测量系统 (PPMS) 是杜克大学的重要补充材料研究基础设施，并将极大地影响科学研究的许多领域，从量子磁性、拓扑效应和紧急现象的基础研究，到纳米磁体和超导纳米结构的电传输，到设计和评估分子、纳米级和宏观材料，再到研究碳中的电子关联性纳米管和石墨烯，用于能源应用的新型有机半导体和混合材料的表征，高温超导体的合成和表征。 PPMS 配备集成传导冷却超导 14 特斯拉磁体。该系统提供无缝温度过渡，能够在 45 分钟内将样品室从室温冷却至 1.8 K，并稳定至优于 0.001 K。稀释制冷机插入件能够进行低至 50 mK 的测量，这对于探测材料中的量子力学现象至关重要。样品室可容纳各种测量插件，所有这些插件都可以在计算机控制下在整个磁场和温度范围内进行全自动数据采集。多功能探头可容纳定制实验，水平样品旋转器可根据样品相对于磁场的方向进行磁阻测量。该系统能够测量电阻率、导热率、比热、霍尔效应和其他热电特性，以及磁化率和磁化强度。该系统的无冷冻剂功能确保了设备经济高效且可靠的长期运行，使其能够适应其所服务的庞大用户群。该奖项反映了 NSF 的法定使命，并通过使用评估被认为值得支持基金会的智力价值和更广泛的影响审查标准。