MRI: Acquisition of PPMS EverCool Dewar, and Heat Capacity and Thermal Transport Probes for Research into Disordered Magnetic Materials at a Predominately Undergraduate Institution

点击翻译按钮获取中文摘要

0922833KiddUniversity of Northern Iowa"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Technical Summary: The PPMS-based instrumentation to be purchased with this grant will be used to measure key magnetic and electronic properties (magnetization, susceptibility, resistivity, specific heat, and thermopower) in low-dimensional materials such as intercalated transition-metal dichalcogenides. The focus will be on materials with relatively simple crystal structures but which provide the ability to tune their physical properties through controlled incorporation of selected impurity atoms. We will examine how disorder and the addition of chemical impurities influence phase transitions or even give rise to new electronic or magnetic ground states. Our intent is to elucidate the fundamental ingredients required for the existence of magnetic and electronic states. In addition to its value for scientific research, the new dewar will drastically reduce liquid helium costs for low-temperature measurements. This will enable the instrument to be used in advanced undergraduate laboratories and summer workshops involving high school teachers and high school students from traditionally underrepresented groups through partnerships via a partnership between the university and the Upward Bound Program. By exposing our undergraduate students to the exotic physics of low temperature systems we will be preparing them not only for scientific careers, but also a world in which nanoscale and other advanced materials will play an ever increasing role in everyday life.Layman Summary: The study of the magnetic and electronic properties of new materials is essential for the continued growth of the U.S. and other modern economies that are based upon the processing, interpretation, and distribution of information. For example, significant improvements in microprocessor speed and magnetic information storage capacity can only be effected by exploiting the knowledge gained through experimental and theoretical investigations of new and existing materials. Materials will also play an essential role as the U.S. and other modern economies move from fossil-fuel-based to renewable energy sources. Examples are higher-efficiency and cheaper solar cells and better (and cheaper) batteries. This project seeks to carefully investigate the magnetic and electronic properties of relatively simple materials with constituents that can be controlled to produce desired behavior. The studies will be carried out under a wide variety of conditions, including low temperatures and high magnetic fields, in order to fully understand the microscopic interactions that give rise to the observed properties. After acquiring a deep understanding of the properties of these materials, we will be in an excellent position to exploit these properties for various applications, including those mentioned above. The equipment that is being requested will allow a wide array of magnetic and electronic measurements while at the same time dramatically lowering the cost of low-temperature measurements through the use of cutting-edge refrigeration technology. Undergraduate students, high-school teachers, and high-school students will be involved in all aspects of the project. Special effort will be dedicated to the engagement of high-school students from underrepresented groups in science-related fields with a view to increasing their participation in such fields at the undergraduate level and beyond.