Terahertz Charge Dynamics in Oxide Films and Heterostructures

氧化膜和异质结构中的太赫兹电荷动力学

• 批准号: 9870258
• 负责人: Joseph Orenstein
• 金额: $ 31.5万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9870258&HistoricalAwards=false
• 关键词: Terahertz; Charge; Dynamics; Oxide; Films

w:\awards\awards96\*.doc 9870258 Orenstein This experimental research project focuses powerful new methods of time-domain terahertz spectroscopy on questions of charge dynamics in oxide thin films. The physics associated with collossal magetoresistance and with cuprate superconductivity are two thrusts of the work. The thin film samples are prepared by several collaborators, with state-of-the-art synthesis methods including reactive electron-beam coevaporation, molecular-beam epitaxy, and ultra-high vacuum pulsed laser-ablation. Measurements of the real and imaginary parts of the electrical conductivity will be made in the range from 100-3000GHz, which lies in a gap between ranges accessible by microwave and FTIR methods. A further aspect of the work involves bilayers of magnetic (M) and superconducting (S) oxides, and trilayer configurations in which M and S layers are separated by thin insulating layers. The ultimate goal of the research is to understand and control electronic transport in designed-to-order multilayer thin films. This research program is interdisciplinary in nature and involves one or more postdoctoral and graduate students, who receive excellent training in preparation for careers in industry, government laboratories or academia. %%% This experimental research project focuses powerful new optical pulse methods to clarify the motions of charge carriers in certain types of oxide thin films. The oxides under investigation show great promise for applications as magnetic sensors or electron devices, or as superconducting elements in a future electronics. The fundamental physics associated with collossal magetoresistance and with cuprate superconductivity are two thrusts of the work. The thin film samples are prepared by several collaborators, with state-of-the-art synthesis methods i ncluding reactive electron-beam coevaporation, molecular-beam epitaxy, and ultra-high vacuum pulsed laser-ablation. Measurements of the electrical conductivity will be made in the range from 100-3000GHz, which lies in a gap between ranges accessible by microwave and Fourier-transform infrared methods. A further aspect of the work involves bilayers of magnetic (M) and superconducting (S) oxides, and trilayer configurations in which M and S layers are separated by thin insulating layers. The ultimate goal of the research is to understand and control electronic transport in designed-to-order multilayer thin films. This research program is interdisciplinary in nature and involves one or more postdoctoral and graduate students, who receive excellent training in preparation for careers in industry, government laboratories or academia. ***

9870258奥伦斯坦这个实验研究项目聚焦于氧化物薄膜中电荷动力学问题的强大的新的时域太赫兹光谱方法。与大肠磁阻和铜酸盐超导电性相关的物理学是这项工作的两个重点。薄膜样品是由几个合作者用最先进的合成方法制备的，包括反应电子束共蒸发、分子束外延和超高真空脉冲激光烧蚀。电导率的实部和虚部的测量将在100-3000 GHz的范围内进行，该范围位于微波和FTIR方法可以到达的范围之间。这项工作的另一个方面涉及磁性(M)和超导(S)氧化物的双层，以及由薄绝缘层分隔M层和S层的三层结构。这项研究的最终目标是了解和控制按订单设计的多层薄膜中的电子输运。这一研究项目本质上是跨学科的，涉及一名或多名博士后和研究生，他们接受了为在工业、政府实验室或学术界就业做准备的出色培训。这个实验研究项目集中了强大的新的光脉冲方法来阐明某些类型的氧化物薄膜中载流子的运动。正在研究的氧化物显示出作为磁性传感器或电子器件的巨大前景，或者作为未来电子产品的超导元素。与巨磁电阻和铜酸盐超导性相关的基本物理学是这项工作的两个重点。薄膜样品是由几个合作者用最先进的合成方法制备的，包括反应电子束共蒸发、分子束外延和超高真空脉冲激光烧蚀。电导率的测量将在100-3000 GHz的范围内进行，这一范围位于微波和傅里叶变换红外方法所能达到的范围之间。这项工作的另一个方面涉及磁性(M)和超导(S)氧化物的双层，以及由薄绝缘层分隔M层和S层的三层结构。这项研究的最终目标是了解和控制按订单设计的多层薄膜中的电子输运。这一研究项目本质上是跨学科的，涉及一名或多名博士后和研究生，他们接受了为在工业、政府实验室或学术界就业做准备的出色培训。***