Highly Ce3+ - doped Glass Material for Advanced Photonic Devices

第一部分：三价铈（Ce（III））掺杂的光学材料具有非凡的光学和物理性质，并且目前代表了用于医学成像、高能粒子和辐射可视化、碰撞束实验中粒子到达的测量时间、中微子和暗物质探测器、以及用于关键基础设施和通信以及照明的抗高水平电离辐射的光学元件。目前，用于上述应用的大多数现有的高度Ce（III）掺杂的材料基于结晶固体（原子在结构内良好有序），因为它们能够容纳大浓度的Ce（III）离子。然而，这些高掺杂晶体的制造工艺复杂、耗时且昂贵，特别是与类似组成的玻璃（其中原子是短程有序的，但在长程内是无序的）相比时。类似地，这种晶体的应用也受到小尺寸、脆性和物理性质随取向的变化的限制。所有这些挑战都可以通过使用高度Ce（III）掺杂的硅酸盐玻璃来解决，与它们的晶体对应物相比，这些玻璃在机械性能、化学耐久性和热稳定性方面提供了改进，并且可以制成大尺寸和复杂的形状（包括拉制成光纤，广泛用于当前的光子系统中）。然而，由于Ce（III）离子的稳定性差，硅酸盐玻璃体系中Ce（III）的掺杂水平通常非常低，限制了它们的应用范围。这项研究的目的是提高这些铈离子在硅酸盐玻璃中的稳定性，以达到前所未有的掺杂水平。新的合成程序的Ce（III）掺杂的硼铝硅酸盐玻璃将被用来理解和探索影响Ce（III）离子的稳定性的因素。 本文将系统研究Ce（III）掺杂量和合成条件对硼铝硅酸盐玻璃物理、光学和发光性能的影响。所获得的知识将有助于开发用于先进光子应用的具有成本效益和鲁棒性的高度Ce（III）掺杂材料。该项目将为材料和光学科学的研究生提供跨学科的培训经验。参与该项目的研究人员和研究生将进一步强调教育推广，旨在通过为本科生提供研究经验和指导来提高对材料和光学科学的兴趣。第2部分：技术总结计划的研究集中在推动Ce（III）掺杂材料的当前掺杂极限远远超过1 mol.% Ce 2 O3的范围目前可以实现。光学材料中的高掺杂水平的Ce（III）离子通常需要低成本、尺寸、重量和功率的光子器件，并且主要用晶体材料实现。然而，这种重掺杂晶体不能批量生产，或者具有太昂贵和耗时的制造工艺。相比之下，硅酸盐玻璃是Ce（III）离子的理想基质，具有成本低、易于生产和规模化、可熔铸成多种形状、具有良好的机械性能、化学稳定性和热稳定性等优点。尽管已经做出了许多努力来将Ce（III）掺入到坚固的硅酸盐玻璃体系中，但在Ce（IV）出现之前，Ce（III）的掺杂水平仍然被限制为小于3.7×10^20 Ce（III）离子/cm 3，使得Ce（III）掺杂的玻璃材料与晶体相比没有竞争力。为了获得高Ce（III）掺杂的硼铝硅酸盐玻璃（10^22离子/cm 3），提出了合成条件、前体化学品和添加剂对铈（III）到铈（IV）转变和玻璃物理性质的影响的系统研究。额外的重点放在开发的玻璃材料的表征，通过研究的光学，光谱，发光，磁光和闪烁性能，缺陷的形成下的伽马射线，以及能量转移的Tb（III），Eu（III）和Mn（II，IV）共掺杂样品正在研究，以评估性能。这种研究方法为研究生提供了一个极好的机会，学习材料和光学研究中使用的尖端实验技术和理论方法，并更广泛地了解材料和光学科学如何解决社会的一些重大挑战，例如，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

PART 1: NON-TECHNICAL SUMMARYTrivalent cerium (Ce(III)) doped optical materials possess extraordinary optical and physical properties and currently represent the state-of-art materials for advanced optical devices that are used in medical imaging, high-energy particles and radiation visualization, measurement time of particles arrival in colliding beam experiments, neutrino and dark matter detectors, and optical elements resistant to high levels ionizing radiation for critical infrastructure and communication, and illumination. Presently, most existing highly Ce(III)-doped materials for the above-mentioned applications are based on crystalline solids (were the atoms are well ordered within the structure) because of their ability to accommodate large concentrations of the Ce(III) ions. However, the fabrication processes for these highly doped crystals are complex, time-consuming, and expensive, particularly when compared with similar composition glasses (where atoms are short-range ordered but disordered within long range). Similarly, applications of such crystals is also restricted by small size, brittleness, and change in physical properties with orientation. All these challenges can be addressed by use of highly Ce(III)-doped silicate glasses that offer improvements in mechanical properties, chemical durability and thermal stability compared ot their crystalline counerparts and can be made into large-size and complex shapes (including drawn into optical fibers, extensively used in current photonic systems). However, the doping levels of Ce(III) in silicate glass systems are typically very low due to poor stability of Ce(III) ions, limiting their range of applications. The aim of this research is to enhance the stability of these cerium ions within silicate glass to achieve unprecedented levels of doping. Novel synthesis procedures of Ce(III)-doped boron-aluminosilicate glass will be employed to understand and explore factors influencing stability of Ce(III) ions. The effect of Ce(III) doping level and synthesis conditions on physical, optical and luminescent properties of boron-aluminosilicate glasses will be systematically studied. The gained knowledge will aid in developing cost-efficient and robust highly Ce(III) -doped materials for advanced photonic applications. The project will provide an interdisciplinary training experience to graduate students in material and optical sciences. The investigators and graduate students involved in this project will further emphasizes educational outreach, aiming to enhance interest in material and optical sciences by offering research experiences and mentorship to undergraduate students. PART 2: TECHNICAL SUMMARYThe planned research is centered on pushing the current doping limits of Ce(III)-doped materials well beyond the 1 mol.% of Ce2O3 range currently achievable. High doping levels of Ce(III) ions in optical materials are usually required for low cost, size, weight, and power photonic devices and have been mostly achieved with crystalline materials. However, such heavily doped crystals cannot be produced in bulk or have too expensive and time-consuming manufacturing processes. Compared to the above, silicate glasses are an ideal host for Ce(III) ions with advantages of low-cost, ease of production and scaling, melt-cast into multiple shapes, and would have favorable mechanical properties, chemical durability and thermal stability. Although numerous efforts have been made to incorporate Ce(III) into robust silicate glass systems, the doping level of Ce(III) is still limited to less than 3.7×10^20 Ce(III) ions/cm3 before Ce(IV) appears, making Ce(III)-doped glass material non-competitive against crystals. To obtain highly Ce(III)-doped boron-aluminosilicate glass (10^22 ions/cm3) a systematic study of the effects of synthesis conditions, precursor chemicals and additives on cerium (III) to cerium (IV) transition and the glass physical properties is proposed. Additional focus is placed on the characterization of the developed glass materials, through study of optical, spectral, luminescence, magneto-optical and scintillation properties, defect formation under gamma rays, as well as energy transfer in Tb (III), Eu(III) and Mn(II,IV) co-doped samples are being studied to evaluate the performance. This research approach provides an excellent opportunity for graduate students to learn cutting edge experimental techniques and theoretical methods used in material and optical research and gain a broader understanding of how material and optical sciences can address some of society’s major challenges, e.g., affordable medical services, nuclear waste management and security.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.