NSF-Europe: Evolution of the Dielectric Constant Across Electronic Transitions

本项目旨在研究钙钛矿相关结构混合价氧化物中的电荷有序（CO）现象，并探索高介电常数材料的设计。将研究介电常数在交叉处从局部电子行为到巡回电子行为的演变。在这一转变中，物理性质的演变仍然是一个广泛而深入的研究课题，因为对于这一转变的特征仍然没有公认的理论，它表现出许多新的现象。令人惊讶的是，介电性质的演变很少受到关注，但它有望提供新的技术兴趣现象。西班牙小组的两名主要研究人员曾在德克萨斯州与Goodenough教授一起工作，因此建立了良好的工作关系。此外，一名美国公民的德克萨斯大学研究生将在西班牙学习。参与的几所大学为这个复杂的问题带来了不同的综合和/或测量技术，每个国家的学生都有一个极好的机会从这种合作中受益文化和科学。设计一种具有异常高介电常数的材料的可能性将打开一个技术和基础兴趣领域。＊＊＊

This project aims to investigate the charge-ordering (CO) phenomenon in mixed-valent oxides with perovskite-related structures and to explore the design of materials with a high dielectric constant. The evolution of the dielectric constant at the crossover from localized to itinerant electronic behavior will be studied. The evolution of physical properties at this transition continues to be a subject of extensive and intensive investigation because there is still no accepted theory of the character of this transition, which manifests a number of novel phenomena. Surprisingly, the evolution of the dielectric properties has received little attention, yet it promises to provide novel phenomena of technical interest. %%% Two of the key investigators of the group in Spain have worked in Texas with Professor Goodenough, so excellent working relationships have been established. In addition, a University of Texas graduate student who is a U.S. citizen will study in Spain. The several universities involved bring different synthetic and/or measurement techniques to this complex problem, and the students of each country have an excellent opportunity to benefit culturally as well as scientifically from this collaboration. The possibility of designing a material with an anomalously high dielectric constant would open a field of technical as well as fundamental interest. ***