MRI: Acquisition of a Cryogen-Free Physical Properties Measurement System (PPMS DynaCool) for Quantum Materials Research and Education at NSU

非技术摘要这一重大研究仪器(MRI)奖将使人们能够购买和安装无低温物理性质测量系统(PPMS)，该系统将用于新量子材料和器件的制造和表征方面的研究和教育培训。该仪器将设在诺福克州立大学麦克德蒙德应用研究中心(MCAR)，供教职员工和学生使用。它也将是汉普顿路地区唯一的同类仪器，MCAR位于中心位置，距离其他六所大学、四所社区学院、托马斯·杰斐逊国家加速器设施、NASA兰利研究中心和东弗吉尼亚医学院只有45分钟的车程，这些学校都不能在当地接触到这种类型的设备。PPMS系统将用于在包括温度和外加磁场在内的精确控制环境中表征基本材料属性和器件性能。这一体系将直接影响至少20名南洋理工大学材料科学与工程研究生项目的硕士和博士研究生以及30多名南洋理工大学本科生STEM专业的教育、研究培训和专业发展，所有参与者大多来自STEM领域传统上代表性较低的群体。这一主要仪器是诺福克州立大学材料研究基础设施的重要补充，将支持各种跨学科材料研究项目，范围包括量子材料的基础研究、非中心对称磁体中新型自旋织构的特征、拓扑效应和临界现象、新型有机半导体和杂化材料的表征、生物医学应用的磁性纳米颗粒以及稀土磁热和磁弹性材料的薄膜。物理性能测量系统配备了集成的传导冷却超导14特斯拉磁体，该磁体被公认为最先进的强磁场和低温系统，具有极高的稳定性和灵敏度。该系统可以在不到40分钟的时间内将样品室从室温冷却到1.9K。稀释式冰箱插件能够进行低至50MK的测量，这对于探索材料中的量子力学现象至关重要。样品室容纳了各种测量插件，所有这些插件都允许在计算机控制下对整个磁场和温度范围进行全自动数据采集。多功能探头可进行定制实验，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。该系统提供了测量电阻率、热导率、霍尔效应和其他热电性能以及磁化率和磁化强度的能力。该系统的闭路循环无制冷剂特性确保了设备的成本效益和可靠的长期运行。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。

Non-Technical AbstractThis Major Research Instrumentation (MRI) award will enable the purchase and installation of a Cryogen-Free Physical Property Measurement System (PPMS) that will be used for research and education training in fabrication and characterization of new quantum materials and devices. The instrument will be located in the Norfolk State University McDemmond Center for Applied Research (MCAR) and will be available for use by faculty and students. It will also be the only instrument of its kind in the Hampton Roads area with MCAR being centrally a location within a 45 minute drive of six other universities, four community colleges, the Thomas Jefferson National Accelerator Facility, the NASA Langley Research Center, and the Eastern Virginia Medical School, none of which have local access to this type of equipment. The PPMS system will be used to characterize both basic materials properties and device performance in an accurately controlled environment including temperature and applied magnetic field. This system will have a direct impact on the education, research training, and professional development of at least 20 MS and PhD students in the NSU material science and engineering graduate programs, and over 30 NSU undergraduate STEM majors with the majority of all the participants coming from groups traditionally underrepresented in STEM fields. The impact on undergraduates will result from individual student research projects and research training through modules developed for advanced laboratory courses.Technical AbstractThis major instrumentation is an important addition to Norfolk State University’s materials research infrastructure and will support diverse interdisciplinary materials research projects ranging from fundamental studies of quantum materials, signatures of novel spin-textures in noncentrosymmetric magnets, topological effects and critical phenomena, characterization of novel organic semiconductor and hybrid materials, magnetic nanoparticles for biomedical applications and thin films of rare-earth magnetocaloric and magneto-elastic materials. The Physical Properties Measurement System is equipped with an integrated conduction-cooled superconducting 14 Tesla magnet which is recognized as state-of-the-art high magnetic field and low-temperature system with exceptional stability and sensitivity. This system can cool the sample chamber from room-temperature down to 1.9 K in less than 40 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, Hall Effect, and other thermoelectric properties, as well as susceptibility and magnetization. The closed-cycle cryogen-free feature of this system ensures cost-effective and reliable long-term operation of the equipment.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.