High-pressure synthesis and crystal growth of the polar metal LiOsO3

极性金属LiOsO3的高压合成与晶体生长

• 批准号: 1905598
• 负责人: Jianshi Zhou
• 金额: $ 13.5万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-15 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1905598&HistoricalAwards=false
• 关键词: pressure; synthesis; crystal; growth; polar

PART I: NON-TECHNICAL SUMMARYCrystals are the basis for many modern technologies. With their high degree of structural perfection and chemically tunable compositions, crystals are at the heart of microelectronics, optics and laser technologies, and photovoltaics. Keeping an edge on the technology of crystal growth for the most advanced materials is a key in US competitiveness in science and technology. This project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, focuses on the growth of crystals of a newly discovered oxide material that includes the rarely studied element osmium. Large, high-quality crystals are needed in order to fully understand the exotic physical properties of this material and the underlying microscopic interactions. The knowledge gained from the project will benefit the design of new functional materials in sensor technology and photovoltaics. Undergraduate students will work on the project and will also be involved in outreach programs such as Alice in Wonderland for female high school students and the annual Explore UT event for students, parents, and teachers. PART II: TECHNICAL SUMMARYThe ilmenite LiOsO3, first reported in 2013, is a polar metallic solid that is an excellent candidate for examining the interplay between metallic and ferroelectric properties. It is metallic to 0.1 K and undergoes a second order non-polar to polar structural transition at 130 K. The transition to a polar structure changes the electronic behavior dramatically, but mobile electrons remain to screen the dipoles from interacting with one another so the polar state is not switchable. How electrons move in the presence of dipoles remains poorly understood. To reveal physical properties reliably, measurements with advanced probes on large, high-quality crystals are necessary, but crystal growth remains a bottleneck in the study of LiOsO3. This project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, aims to grow high quality, large crystals of LiOsO3 by using high-temperature and high-pressure conditions. The crystal growth will be enhanced by (1) mapping the growth conditions in the pressure-temperature phase diagram and (2) optimal selection of the starting materials and flux. Crystal quality will be checked by Laue back reflection and X-ray diffraction rocking-curve scans. Crystals grown in this project will be not only studied in the PI's lab, but also provided to other research laboratories with advanced characterization facilities but lacking the means for crystal growth under high pressure, which will contribute to the broader impacts of the research. Undergraduate students will work on the project and will also be involved in outreach programs such as Alice in Wonderland for female high school students and the annual Explore UT event for students, parents, and teachers.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.

第一部分：非技术和晶体是许多现代技术的基础。晶体具有高度的结构完美性和化学可调成分，是微电子、光学和激光技术以及光伏技术的核心。在最先进材料的晶体生长技术上保持优势是美国科技竞争力的关键。该项目由材料研究部的固态和材料化学计划支持，重点是一种新发现的氧化物材料的晶体生长，其中包括很少被研究的元素Os。为了充分了解这种材料的奇异物理性质和潜在的微观相互作用，需要大的、高质量的晶体。从该项目中获得的知识将有助于传感器技术和光伏领域的新功能材料的设计。本科生将参与该项目，还将参与扩展项目，如面向女高中生的爱丽丝梦游仙境，以及面向学生、家长和教师的一年一度的探索UT活动。第二部分：技术总结2013年首次报道的钛铁矿LiOsO_3是一种极性金属固体，是研究金属和铁电性能之间相互作用的极佳候选者。它是金属的，温度为0.1K，并在130K经历了二级非极性结构到极性结构的转变，转变为极性结构，极大地改变了电子行为，但移动电子保留了屏蔽偶极相互作用的作用，因此极态是不可切换的。电子在偶极子存在的情况下是如何运动的，目前还知之甚少。为了可靠地揭示物理性质，使用先进的探针对大尺寸、高质量的晶体进行测量是必要的，但晶体生长仍然是研究碳酸锂的瓶颈。该项目得到材料研究部固态和材料化学计划的支持，旨在通过高温高压条件生长高质量的大晶体三氧化锂。通过(1)在压力-温度相图中绘制生长条件图和(2)对起始材料和助熔剂的优化选择，将促进晶体生长。晶体质量将通过劳厄背反射和X射线衍射摇摆曲线扫描进行检查。在该项目中生长的晶体不仅将在PI的实验室进行研究，还将提供给其他拥有先进表征设备但缺乏高压下晶体生长手段的研究实验室，这将有助于该研究的更广泛影响。本科生将参与该项目，还将参与扩展项目，如面向女高中生的爱丽丝漫游仙境，以及面向学生、家长和教师的年度探索UT活动。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Strongly correlated electrons in the ferroelectric metal LiOsO3

• DOI: 10.1103/physrevb.104.115130
• 发表时间: 2021-09
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: J. Zhou;X. Li;J. M. He;J. Chen;K. Yamaura

Room-temperature polar metal stabilized under high pressure

• DOI: 10.1103/physrevb.101.220101
• 发表时间: 2020-06
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: J. Gao;S. Fu;K. Yamaura;J. Lin;J. Zhou

Unraveling the Orbital Physics in a Canonical Orbital System KCuF3

解开正则轨道系统 KCuF3 中的轨道物理原理

• 发表时间: 2021
• 期刊: Physical review letters
• 影响因子: 8.6
• 作者: Li, Jiemin;Xu, Lei;Garcia-Fernandez, Mirian;Nag, Abhishek;Robarts, H. C.;Walters, A. C.;Liu, X.;Zhou, Jianshi;Wohlfeld, Krzysztof;van den Brink, Jeroen
• 通讯作者: van den Brink, Jeroen