CAREER: Tuning Electronic Phases in Layered Complex Oxides

这个CAREER项目是由电子和光子材料和陶瓷计划共同资助的。技术支持：该CAREER项目的主要范围旨在合成和表征具有强电子相关性的纳米结构复合钙钛矿氧化物薄膜。控制这些系统中的电子相变需要具有大大降低的缺陷密度、纳米级载流子限制的多层膜和原子级尖锐界面的优异材料质量。研究的重点是人工层状结构，以实现低维电子液体在极端的载流子浓度的限制。采用混合分子束外延生长量子阱异质结构，其中使用非极性界面处的能带不连续性来实现限制。我们的目标是探索如何在薄膜生长，即应变，尺寸限制，化学掺杂和分层方案，材料设计参数影响这些二维电子液体的电子相的稳定性。先进的光谱和结构表征技术与温度相关的热电和热磁以及磁输运特性相结合，将费米表面改性与这些人工电子材料系统的原子尺度设计相关联。非技术性：该项目解决了氧化物电子学新兴领域的基本问题和基础研究挑战。理解由强电子相关引起的现象提供了一条发现、定制和利用具有超越传统半导体材料的功能的电子材料的途径。研究结果预计将对未来计算方案的节能和超快逻辑器件的发展产生重大影响。该项目活动包含一个强大的教育和推广嵌入在宾夕法尼亚州立大学现有的推广计划的组成部分。两个互动演示包创建，以说明科学和技术的概念相关的研究。建立了分子束外延系统的功能模型模拟，允许年轻学生使用代表原子的球形物体生长分层结构。一个直观和有形的互动包节拍器的开发，以帮助探索相关性的影响，使用节拍器的同步行为的各个方面，概念化耦合的基础上相互作用。示范套组设计灵活，可灵活运用于各种外展活动，包括博物馆展览、教室和工作坊活动，以及科学节。

This CAREER project is jointly funded by Electronic and Photonic Materials and Ceramic programs. Technical: The main scope of this CAREER project aims to synthesize and characterize nanostructured complex perovskite oxide thin films exhibiting strong electron correlation. Controlling electronic phase transitions in these systems requires excellent materials quality with greatly reduced defect densities, nanoscale carrier confinement of ultrathin layers and atomically sharp interfaces. Research is focused on artificial layered structures to achieve low dimensional electron liquids in the limit of extreme carrier concentrations. Hybrid molecular beam epitaxy is employed to grow quantum well heterostructures, where the confinement is achieved using band discontinuities at nonpolar interfaces. The goal is to explore how materials design parameters available in thin film growth, namely strain, dimensional confinement, chemical doping and layering scheme, affect the stability of the electronic phases of these two-dimensional electron liquids. Advanced spectroscopic and structural characterization techniques are employed in combination with temperature-dependent thermoelectric and thermomagnetic as well as magneto-transport properties to correlate Fermi surface modifications with atomic scale design of these artificial electronic material systems. Non-technical: The project addresses fundamental questions and basic research challenges in the emerging field of oxide electronics. Understanding phenomena arising from strong electron correlation provides a path to discover, tailor and utilize electronic materials with functionalities beyond conventional semiconductor materials. Research results are expected to significantly impact the development of energy-efficient and ultrafast logic devices for future computation schemes. The project activities contain a strong educational and outreach component embedded in the existing outreach programs at Penn State. Two interactive demonstration packages are created to illustrate scientific and technological concepts relevant to the research. A functional model analog of a molecular beam epitaxy system is built allowing young students to grow layered structures using spherical objects representing atoms. An intuitive and tangible interactive package of metronomes is developed to help exploring various aspects of correlation effects using the synchronization behavior of metronomes to conceptualize coupling based on mutual interactions. The flexible design of the demonstration packages allow versatile utilization for a variety of outreach activities, including museum exhibits, class room and workshop activities, and science festivals.