Optical Spectroscopy of Excitons in Correlated Electron Systems

DMR-9510699 Heiman 利用稳态和时间分辨光学技术研究了砷化镓基强关联二维电子在强磁场和低温下的态。 感兴趣的研究包括不受价带空穴扰动的不可压缩量子液体的研究，电子固体以及复合费米子的研究，以及具有宽抛物量子威尔斯的准三维电子系统的研究。 当在极低的低温和超高磁场条件下进行研究时，限制在半导体界面上的电子态表现出不寻常的特性。 这些系统揭示了新的和完全出乎意料的行为，继续研究可能会产生进一步的见解高度相关的电子系统的属性。 测量这些属性是内在的科学兴趣，但也有希望发现新的技术应用。 目前的调查协调强大的光学表征技术的优势，在超低温与国家的最先进的半导体材料制备。

DMR-9510699 Heiman Strongly correlated two dimensional electron states based on gallium arsenide are investigated in high magnetic fields using steady state and time-resolved optical techniques and low temperatures. Investigations of interest include study of the incompressible quantum liquid without perturbation by valence band holes, study of the electron solid as well as composite fermions, and the study of quasi-three dimensional electron systems with wide parabolic quantum wells. %%% Electron states confined to the interfaces of semiconductors exhibit unusual properties when investigated under conditions of very low cryogenic temperatures and ultra high magnetic fields. These systems have revealed new and completely unexpected behavior and continued studies are likely to yield further insights into the properties of highly correlated electron systems. Measurement of such properties is of intrinsic scientific interest but also holds the promise for discovery of novel technological applications. The current investigations coordinate the strengths of powerful optical characterization techniques at ultra low temperatures with state-of-the-art semiconductor materials preparation.