GOALI: Structure-Property Systematics in Novel Chalcogenide glasses with Modified Networks

非技术描述：Ge、as、Sb和P的硫化物、硒化物和碲化物（即硫族化物）等玻璃材料在光电子、电信、存储、替代能源和环境遥感等领域得到了广泛的应用。这些材料的原子结构具有共价键原子网络的典型特征，并详细研究了这些网络硫系玻璃的结构-性能关系。在加入Ba和Ga等元素后，这些网络的物理和化学特性可以得到实质性的改变。人们对这些新材料的独特性质知之甚少，它们可能会带来变革性的、广泛的技术应用。该研究项目汇集了来自加州大学戴维斯分校和康宁公司（世界上最重要的尖端玻璃技术的创新者和商业开发商）的互补专业知识和共同兴趣的研究人员，研究这些新型硫系材料的基本结构-性能关系。该项目最终将能够制定预测模型，以优化这些材料，改善潜在商业化的功能。这个研究项目的学生正在学习调查工业应用背后的“基础科学”领域的问题。该项目为学生在学术和工业环境中提供强大的实验技能和研究经验，这将为他们的职业生涯打开许多机会。该项目与加州大学戴维斯分校的少数族裔服务和其他外展项目相协调，以吸引和招募代表性不足的研究生，并提高学生对玻璃材料科学和技术的认识。技术细节：该项目需要研究结构-性能关系，并在原子尺度上理解新型改性和补偿网络三元和四元硫系大块玻璃、纤维和Ba-Ga-Ge-Se体系中的过冷液体在玻璃化转变附近的输运和弛豫结构机制。要实现这一目标，需要应用最先进的物理特性测量、结构和动态表征技术的强大组合，包括核磁共振（NMR）、拉曼、光学吸收和荧光光谱、高能x射线衍射和反向蒙特卡罗模拟。这些结果正在结合起来开发预测模型，将原子结构和动力学与宏观物理性质联系起来，这对于这些材料的成分优化至关重要，可用于广泛的技术应用。其中一个例子是探索光子学的潜在应用，这些材料可以作为具有低声子能量和高量子效率的高效稀土宿主。该项目的跨学科性质影响了材料科学与工程、固态化学和物理，并结合了对研究生在最先进的光谱、衍射和模拟技术方面的重要培训。加州大学戴维斯分校、康宁公司、国家强磁场实验室和阿贡国家实验室的设备和专业知识为学生提供了各种现代研究工具和学习使用它们的支持结构。它继续促进我们与工业界、学术界和国家实验室的科学家的长期合作，并通过合作科学家和参与学生之间的大量科学对话和互动，丰富研究生教育和培训经验。资助：本国家科学基金项目由工程局和数学与物理科学局共同资助。

NON-TECHNICAL DESCRIPTION: Glassy materials such as sulfides, selenides and tellurides (i.e. chalcogenides) of Ge, As, Sb and P have found wide-ranging applications in the areas of photonics, telecommunication, memory storage, alternative energy resources and environmental remote sensing. The atomic structures of these materials are typically characterized by a network of covalently bonded atoms and structure-property relationships in these network chalcogenide glasses have been studied in detail. The physical and chemical characteristics of these networks can be substantially modified upon incorporation of elements such as Ba and Ga. Little, if any, is known about the unique properties of these new materials - they could result in transformative and wide-ranging technological applications. This research project brings together investigators with complementary expertise and common interests from UC Davis and Corning Incorporated (the world's foremost innovator and commercial developer of cutting-edge glass technology) to investigate the fundamental structure-property relationships in these novel chalcogenide materials. This project will finally enable the formulation of predictive models necessary for the optimization of these materials towards improved functionalities for potential commercialization. Students in this research project are learning to investigate problems in the realm of "basic science" that underlies industrial applications. The project is preparing students with powerful experimental skills and research experience in both academic and industrial settings that will open many opportunities for their careers. This project coordinates with the underrepresented minority-serving and other outreach programs at UC Davis to attract and recruit underrepresented graduate students and to increase the awareness of students in the science and technology of glassy materials. TECHNICAL DETAILS: This project entails studying the structure-property relationships and developing an atomic scale understanding of the structural mechanisms of transport and relaxation near the glass transition in novel modified and compensated network ternary and quaternary chalcogenide bulk glasses, fibers and supercooled liquids in the Ba-Ga-Ge-Se system. Accomplishing this goal involves application of a powerful combination of state-of-the-art techniques of physical property measurement and structural and dynamical characterization including nuclear magnetic resonance (NMR), Raman, optical absorption and fluorescence spectroscopy, high-energy X-ray diffraction and reverse Monte Carlo simulation. The results are being combined to develop predictive models, linking the atomic structure and dynamics with macroscopic physical properties that are crucial for compositional optimization of these materials for a wide range of technological applications. One example is exploring potential applications in photonics where these materials serve as efficient rare earth hosts with low phonon energy and high quantum efficiency. The interdisciplinary nature of this project impacts materials science and engineering, solid-state chemistry and physics and incorporates significant training of graduate students in state-of-the-art spectroscopic, diffraction and simulation techniques. The equipment and expertise at UC Davis, Corning Inc., National High Magnetic Field laboratory and Argonne National Laboratory provide students with a variety of modern research tools and a supportive structure for learning to use them. It continues to foster our longstanding collaborations with scientists in industry, academia and national laboratories and enriches the graduate education and training experience through numerous scientific dialogue and interactions between the collaborating scientists and participating students.FUNDING: This National Science Foundation project is co-funded by the Engineering Directorate and the Mathematical and Physical Sciences Directorate.