Terahertz Charge Dynamics in Oxide Films and Heterostructures

本实验研究项目将时域太赫兹光谱学的强大新方法应用于氧化薄膜中的电荷动力学问题。与巨磁阻和铜超导有关的物理学是这项工作的两个重点。薄膜样品是由几位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测量将在100-3000GHz范围内进行，该范围位于微波和FTIR方法可达到的范围之间的间隙。这项工作的另一个方面涉及磁性(M)和超导(S)氧化物的双层结构，以及M层和S层被薄绝缘层隔开的三层结构。研究的最终目标是了解和控制电子输运的设计有序多层薄膜。该研究项目是跨学科的，涉及一名或多名博士后和研究生，他们接受了良好的培训，为工业、政府实验室或学术界的职业生涯做准备。这个实验研究项目的重点是强大的新光脉冲方法来阐明某些类型的氧化薄膜中载流子的运动。正在研究的氧化物在磁性传感器、电子器件或未来电子产品中的超导元件方面显示出巨大的应用前景。与巨磁阻和铜超导有关的基础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100-3000GHz范围内进行，该范围位于微波和傅里叶变换红外方法可达到的范围之间的间隙。这项工作的另一个方面涉及磁性(M)和超导(S)氧化物的双层结构，以及M层和S层被薄绝缘层隔开的三层结构。研究的最终目标是了解和控制电子输运的设计有序多层薄膜。该研究项目是跨学科的，涉及一名或多名博士后和研究生，他们接受了良好的培训，为工业、政府实验室或学术界的职业生涯做准备。＊＊＊

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. ***