Solid-State Oxides and Oxide-Fluorides

固态氧化物和氧化物-氟化物

• 批准号: 1608218
• 负责人: Kenneth Poeppelmeier
• 金额: $ 46万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608218&HistoricalAwards=false
• 关键词: Solid; State; Oxides; Oxide; Fluorides

Non-Technical AbstractHighly-efficient non-linear optical (NLO) materials are essential to act as waveguides for electrooptic applications. Such materials are used in ultrafast laser spectroscopy and, more recently, to generate ultraviolet laser light for nanolithographic applications. Current research and engineering activities in the field of NLO materials typically concern synthesis of NLO crystals; however, research is needed for understanding how to design NLO materials and why materials exhibit a particular NLO response. While exploring the fundamental driving factors for creation of new NLO materials, research will be performed to grow large (on the order of one cubic centimeter) single crystals to allow a quantitative understanding of the interaction of light with the NLO material. These analyses of basic principles by graduate students and postdoctoral associates -- who are also engaged in local education, teaching, mentoring, and leadership -- will enhance scientific progress and promote commercial expansion of this technologically important field.Technical AbstractEmerging technologies require high-performance nonlinear optical (NLO) materials that exhibit enhanced optical properties at the microscopic and macroscopic level. The rational design of crystal structures, in particular noncentrosymmetric materials, and how to target polar, polar-chiral, and chiral structures, is an ongoing theme in crystal engineering. A new class of potentially high performance NLO inorganic materials, solid-state oxide-fluorides, has been identified. These studies demonstrate that i) the use of fluoride ligands with early-transition metals enhances the second-order Jahn-Teller distortion in comparison to pure oxide compounds, ii) the synthesis of noncentrosymmetric materials can be promoted with the use of polar basic-building units, and iii) the synthesis of compounds that contain two separate anionic building units is likely to result in a noncentrosymmetric compound. These materials comprise a large and new class of solids with properties associated with piezoelectricity, pyroelectricity, ferroelectricity and second harmonic generation (SHG). The structure-property relationships that give rise to high, low, or null nonlinearities of the NLO materials will be examined. Finally, the growth of large crystals (on the order of one cubic centimeter) allows detailed analysis with measurements of the NLO tensor and phase-matchability properties, and other properties of interest such as piezoelectricity. The materials synthesized will have potential use in relaxor ferroelectrics and non-linear optics. These materials will have a high damage threshold and the potential to fabricate large, single crystals suitable for optical use and technical applications. The project is supported by the Solid State and Materials Chemistry Program in the Division of Materials Research.

非技术摘要高效非线性光学 (NLO) 材料对于充当电光应用的波导至关重要。此类材料用于超快激光光谱，最近还用于产生用于纳米光刻应用的紫外激光。当前 NLO 材料领域的研究和工程活动通常涉及 NLO 晶体的合成；然而，需要进行研究来了解如何设计 NLO 材料以及为什么材料表现出特定的 NLO 响应。在探索创造新的非线性光学材料的基本驱动因素的同时，将进行研究以生长大型（约一立方厘米）单晶，以便定量了解光与非线性光学材料的相互作用。研究生和博士后研究员（他们也从事当地的教育、教学、指导和领导）对基本原理的分析将促进科学进步并促进这一重要技术领域的商业扩张。技术摘要新兴技术需要高性能非线性光学（NLO）材料在微观和宏观层面表现出增强的光学特性。晶体结构的合理设计，特别是非中心对称材料，以及如何针对极性、极性手性和手性结构，是晶体工程的一个持续主题。一类新的潜在高性能非线性光学无机材料——固态氧化物氟化物——已经被发现。 这些研究表明，i）与纯氧化物相比，使用具有早期过渡金属的氟化物配体增强了二阶 Jahn-Teller 畸变，ii）使用极性基本结构可以促进非中心对称材料的合成单元，以及 iii) 包含两个独立阴离子结构单元的化合物的合成可能会产生非中心对称化合物。这些材料由一大类新型固体组成，具有与压电、热电、铁电和二次谐波产生 (SHG) 相关的特性。将检查导致非线性光学材料的高、低或零非线性的结构-性能关系。最后，大晶体（大约一立方厘米）的生长允许通过测量非线性光学张量和相位匹配特性以及其他感兴趣的特性（例如压电性）来进行详细分析。 合成的材料将在弛豫铁电体和非线性光学中具有潜在的用途。这些材料将具有高损伤阈值，并有可能制造适合光学用途和技术应用的大型单晶。该项目得到了材料研究部的固态和材料化学项目的支持。