Magnetotransport and Millimeter Wave Spectroscopy of a Partially Filled Landau Level

小行星9705521 本实验研究项目是对分数维电子气的磁输运和毫米波光谱的研究。 量子 霍尔效应机制， 特别是在部分填充的朗道能级中复合费米子的性质。这些实验为量子霍尔系统的动力学研究打开了一扇新的窗口。我们将研究束缚态的内部结构，即束缚态的色散w（q）和束缚态的内在涨落。 能量在1- 10 K范围内可调的毫米波将通过表面金属光栅或周期性密度调制耦合到2-D气体中，并且将采用灵敏的微分光电导技术。 用于检测。 实验还将涉及纳米结构技术，如高分辨率电子束光刻和加工。 这个实验研究项目致力于研究导电电子系统在二维平面区域内的基本性质。这样一组在低温和高磁场下的受限电子表现出一组非常不寻常的特性，在某些方面，相关的实体不是电子，因为它们在真空中的行为，而是具有可分离的自旋和电荷性质的“准粒子”。这种情况下的“复合费米子”将通过向它们照射无线电波并进行测量来确定对无线电波的响应来进行研究。一方面，这些实验将提供有关电子的新的基本信息， 它们在低温下在受限层中相互作用。另一方面，在这些实验中使用的器件结构类似于在GaAs技术中的先进微电子器件中使用的器件结构。 这项研究将涉及学生谁将在物理领域训练有素，也将获得熟悉半导体器件技术，谁将在工业，政府或教育就业的优秀培训。 ***

9705521 Du This experimental research project is a study of magnetotransport and millimeter wave spectroscopy of the 2-D electron gas in the fractional quantum Hall effect regime, specifically the properties of composite Fermions in a partially filled Landau level. The experiments open a new window to probe dynamics of the quantum Hall system. The internal structure, ie, the dispersion w(q) of the bound states, and the inherent fluctuations of the bound states, will be investigated. Millimeter waves tunable in energy from 1-10K will couple into the 2-D gas via a surface metal grating or periodic density modulation, and a sensitive differential photoconductivity technique will be used for detection. The experiments will also involve nanostructure techniques such as high-resolution electron-beam lithography and processing. %%% This experimental research project is devoted to basic properties of a conducting electron system when confined into a two- dimensional planar region. Such a confined set of electrons at low temperatures and with high magnetic fields exhibits a very unusual set of characteristics, and in some ways the entities which are relevant are not electrons behaving as they behave in vacuum, but "quasi-particles" having separable spin and charge properties. The "composite Fermions" of this situation are to be studied by shining radio waves onto them and making measurments to determine the response to the radio waves. On the one hand the experiments will provide new basic information about electrons when they are in interaction in confined layers at low temperatures. On the other hand the device structures which are used in these experiments are similar to those used in advanced microelectronic devices in the GaAs technology. This research will involve students who will be well trained in the area of physics and will also gain familiarity with semiconductor device technolgy, and who will be excellently trained for employment in industry, government, or education. ***