MRI/RUI: Acquisition of Instrument Suite for Single Crystal Preparation

该奖项是为了收购一套通过助熔剂生长制备金属间化合物单晶的仪器。助熔剂生长是一种强大的技术，可以生产各种各样的同成分熔化和不一致熔化化合物的高质量单晶。这些仪器包括在生长前使金属合金化的电弧炉、在较高温度下生长晶体的管式炉、在较低温度下生长晶体的箱式炉、准备测量用晶体的锯和抛光机、对准备好的样品进行退火的真空退火炉、带数码相机的显微镜和精密天平。由此产生的晶体将使用格林内尔学院已经提供的其他NSF资助的仪器进行表征。粉末X射线衍射仪提供结构信息，而Quantum Design PPMS-9物理特性测量系统提供各向异性直流磁化强度、交流磁化率、电阻率、磁阻率和热容数据。这些仪器支持由首席研究员、格林内尔大学的本科生和艾姆斯实验室的研究人员进行的长期合作研究工作。单晶制备仪器套件将支持的合作研究项目的例子包括研究稀土金属间化合物单晶的磁各向异性和设计单晶形式的强各向异性自旋玻璃，用作测试自旋玻璃理论的模型系统。因为研究总是与教学相结合，在格林内尔，单晶制备仪器将有广泛的影响超出了他们支持的研究项目。学生将使用这些仪器与首席研究员，教师指导的独立学生项目，并在物理专业采取的高级课程实验合作研究。格林内尔学院有一个大的，成功的物理课程，每年毕业10至16个物理专业，其中一半以上的人去研究生院在科学或工程。格林内尔学院已经获得了国家的认可，其成功的努力，以增加通过新科学项目等计划在科学代表性不足的群体的保留。单晶制备仪器套件将有助于扩大这些代表性不足的群体在其教育和研究培训中对研究质量仪器的接触。

This award is for the acquisition of a suite of instruments to prepare single crystals of intermetallic compounds by flux growth. Flux growth is a powerful technique that can produce high-quality single crystals of a wide variety of both congruently melting and incongruently melting compounds. The instruments include an arcmelter to alloy metals prior to growth, a tube furnace to grow crystals at higher temperatures, a box furnace to grow crystals at lower temperatures, saws and polishers to prepare crystals for measurement, a vacuum annealing furnace to anneal prepared samples, a microscope with digital camera, and a precision balance. The resulting crystals will be characterized using other NSF-funded instruments already at Grinnell College. A powder X-ray diffractometer provides structural information, while a Quantum Design PPMS-9 Physical Properties Measurement System provides anisotropic dc magnetization, ac susceptibility, resistivity, magnetoresistivity, and heat capacity data. These instruments support a long-standing collaborative research effort pursued by the principal investigator, undergraduates at Grinnell, and investigators at Ames Laboratory. Examples of collaborative research projects that the single crystal preparation instrument suite will support include studies of magnetic anisotropy in rare earth intermetallic single crystals and the design of a strongly anisotropic spin glass in single crystal form, used as a model system for testing spin glass theories. Because research is always blended with teaching at Grinnell, the single crystal preparation instruments will have broad impact beyond the research projects that they support. Students will use these instruments in collaborative research with the principal investigator, faculty-mentored independent student projects, and experiments in upper-level courses taken by physics majors. Grinnell College has a large, successful physics program, graduating 10 to16 physics majors per year, over half of whom go on to graduate school in science or engineering. Grinnell College has attained national recognition for its successful efforts to increase the retention of underrepresented groups in science through programs such as the New Science Project. The single crystal preparation instrument suite will help to broaden the exposure of these under-represented groups to research-quality instrumentation in their education and research training.