MRI: Acquisition of a Positron Annihilation Lifetime Spectrometer for Enhanced Materials Characterization

该仪器的获取提供了最先进的正电子湮没寿命谱能力，用于在(亚)纳米尺度上对材料的空穴结构进行高级本科生研究和表征。该设备将填补奥斯汀佩伊州立大学材料表征基础设施的关键空白，提供关于有机、无机和生物物质中无电子密度位置(例如，气孔、空洞、空位和其他缺陷)的重要信息。它将极大地促进在生物医学应用材料、电信、能量存储和转换、信息处理和存储、传感器、光电子学和光电子学等新兴领域的跨学科教员活动。该仪器将被指定为共享设施，不仅服务于内部研究需求，还服务于其他学术机构和从事材料科学学科工作的地区性小企业的需求。作为美国罕见的设施(与定期使用它的欧洲、中国或日本相比)，它具有国际和国内产学研合作开发新先进材料的潜力，促进田纳西州和全国材料科学的进步。参与研究项目的本科生将接触到材料科学和粒子物理的尖端知识，这将增加他们在劳动力市场和未来工作中的竞争力。他们还将获得在辐射物理中使用现代实验技术和全球方法的经验。这项提案要求获得资金，以购买正电子湮没寿命谱(PALS)的皮秒计时系统，时间分辨率为200ps(或更高)，探测器组件可调，以及快速方便的数据采集系统。PALS将用于研究晶体、玻璃、液体、聚合物和复合材料中的空间异质性。它作为结构表征方法的补充技术，能够探测从原子尺度到几十纳米大小的开孔和闭孔，以及电荷分布。特别是，这项技术对于无序材料(如玻璃、陶瓷)的研究是有价值的，众所周知，无序材料的物理性质不仅取决于它们的原子子系统，而且还取决于由于其合成/制备的非平衡条件而不可避免地出现的空穴。PALS能力将显著改善奥斯汀佩伊州立大学(APSU)正在进行的研究活动，提高性质和质量，并使新的科学和方向成为可能。作为一种尖端仪器，它将用于教育和培训本科生的物理，以及化学和生物，这将提高APSU的能力，以满足其教育使命。研究人员计划将PALS带来的科学突破纳入本科课程，并将加强与田纳西州和全国各地的K-12学生、产业界、国家实验室和学术界的联系。拥有这一工具将使APSU成为一个对国内和国际合作更具吸引力的机构，这将使学生交换和REU项目以及联合研究项目成为可能。PALS仪器作为共享设施，也将加强TN领域对空穴结构表征的研究能力。

The instrument acquisition provides state-of-the-art capability of positron annihilation lifetime spectroscopy for advanced undergraduate research and characterization of the materials' void structure at (sub)nanoscale. The equipment will fill in a critical gap in the materials characterization infrastructure at Austin Peay State University, providing a vital information on the electron density-free sites (e.g. pores, voids, vacancies and other defects) in organic, inorganic, and biological substances. It will significantly boost interdisciplinary faculty activity in such emerging areas as materials for biomedical applications, telecommunication, energy storage and conversion, information processing and storage, sensors, photonics, and optoelectronics. The instrument will be designated as a shared facility, serving not only the internal research needs, but also the needs of other academic institutions and regional small businesses working in materials science disciplines. Being a rare facility in USA (compare to Europe, China or Japan, where it is used on a regular basis), it has a potential for international and domestic industry-university partnership to develop new advanced materials, promoting the progress of materials science in Tennessee and across the nation. Undergraduate students participating in the research projects will be exposed to cutting-edge knowledge in materials science and particle physics, which will increase their competitiveness on the labor market and future endeavors. They will also gain an experience of using the modern experimental techniques and worldwide approaches in radiation physics. This proposal requests funds to acquire a picosecond timing system for positron annihilation lifetime spectroscopy (PALS) with 200 ps (or better) time resolution, adjustable detectors assembly, and quick and convenient data acquisition system. PALS will be used for studying the spatial heterogeneities in crystals, glasses, liquids, polymers, and composites. It serves as a complementary technique to structural characterization methods, capable of probing both open and closed pores of sizes ranging from atomic scale to several tens of nanometers, as well as the electric charge distribution. Especially, this technique is valuable for the investigations of disordered materials (e.g. glasses, ceramics), which physical properties are known to be determined not only by their atomic sub-system, but also by voids which inevitably appear as a result of non-equilibrium conditions of their synthesis/preparation. PALS capability will significantly improve the ongoing research activity at Austin Peay State University (APSU), enhance the nature and quality, as well as enable new science and directions. As a cutting-edge instrument, it will be used to educate and train undergraduate students in physics, as well as chemistry and biology, which will increase the APSU ability to satisfy its educational mission. The researchers plan to incorporate scientific breakthroughs made possible by PALS into undergraduate curriculum, and will strengthen their outreach to K-12 students, industry, national labs and academia, in Tennessee and across the nation. Having this instrument will make APSU a more attractive institution for domestic and international collaboration, which will enable students exchange and REU programs, as well as joint research projects. The PALS instrument, as shared facility, will also enhance the capabilities of research in TN area towards void structure characterization.