Collaborative Research: FRG: Local Dynamic Origins of Relaxor Ferroelectricity

我们由匹兹堡大学和宾夕法尼亚州立大学的成员组成的重点研究小组将试图了解“弛豫”铁电的物理基础。我们的研究将探索弛豫相和其他母相之间的边界。我们将研究单晶块体材料和分子束外延生长的薄膜。我们将使用新的测量技术，同时探测松弛患者的空间和时间行为。拟议中的实验将为理论注入亟需的经验约束。这项工作的影响将是根本性的和实际的。弛豫行为广泛存在于铁电材料中，但人们对此知之甚少。同时，弛豫单晶可以表现出1%的大的非滞后应变，90%的机电耦合，突出的介电和极化性能，远远超过大多数合适的铁电材料。这项研究工作的跨学科性质，涉及物理学和材料科学的强耦合，将增强主修这两个学科的学生的体验。我们的重点研究小组将试图了解“弛豫”铁电的物理基础。弛豫体的行为与传统铁电材料的性质不同，表现在对电场的频率响应和相关特性方面，例如发生的压电驱动的形状变化。我们的研究将探索弛豫相和其他母相之间的边界。我们将研究单晶块体材料和分子束外延生长的薄膜。我们将使用新的测量技术，以高空间和时间分辨率同时探测弛豫体的行为。拟议中的实验将为理论注入亟需的经验约束。这项工作的影响将是根本性的和实际的。弛豫行为广泛存在于铁电材料中，但人们对此知之甚少。这项研究工作的跨学科性质，涉及物理学和材料科学的强耦合，将增强主修这两个学科的学生的体验。

Our focused research group with members from the University of Pittsburgh and Pennsylvania State University will attempt to understand the physical basis of "relaxor" ferroelectricity. Our investigations will explore the boundary between the relaxor phase and other parent phases. Both single crystal bulk materials and MBE-grown thin films will be investigated. We will use novel measurement techniques that simultaneously probe both spatial and temporal behavior of relaxors. The proposed experiments will infuse much-needed empirical constraints into theory. The impact of this work will be both fundamental and practical. Relaxor behavior is prevalent in a wide class of ferroelectric materials, and is poorly understood. At the same time, relaxor single crystals can exhibit large, non-hysteretic strains 1%, electromechanical coupling 90% and outstanding dielectric and polarization values, performance that far exceeds most proper ferroelectrics. The cross-disciplinary nature of this research effort, involving a strong coupling of physics and material science, will enhance the experiences of students majoring in either discipline. Our focused research group will attempt to understand the physical basis of "relaxor" ferroelectricity. The behavior of relaxors is qualitatively different from conventional ferroelectric materials, in terms of the frequency-dependent response to electric fields and related properties such as the piezoelectrically driven shape changes that occur. Our investigations will explore the boundary between the relaxor phase and other parent phases. Both single crystal bulk materials and MBE-grown thin films will be investigated. We will use novel measurement techniques that simultaneously probe the behavior of relaxors with high spatial and temporal resolution. The proposed experiments will infuse much-needed empirical constraints into theory. The impact of this work will be both fundamental and practical. Relaxor behavior is prevalent in a wide class of ferroelectric materials, and is poorly understood. The cross-disciplinary nature of this research effort, involving a strong coupling of physics and material science, will enhance the experiences of students majoring in either discipline.