US-France Cooperative Research: Electronic and Opto- electronic Properties of 3-5 Compound

该奖项将支持乔治亚理工学院Richard J. Higgins博士及其研究小组与法国图卢兹国家科学应用研究所固体物理实验室J. C. Portal博士之间的合作研究。Drs。Higgins和Portal将研究3-5种化合物半导体异质结构的电子和光电子特性。该研究将强调相干（量子）电子效应，并确定抑制量子电子器件的生长和处理问题。将研究两种测试系统：(a)通过分子束外延生长的耦合量子阱结构，其负差分电阻有望实现亚皮秒开关；但其应用受到物理行为理解不足和(b)电子束光刻的纳米尺度结构可以表现出相相干弹道输运的阻碍。美国和法国的研究人员在异质结构磁输运方面有着积极的合作和共同的研究目标。技术包括探测电子行为的磁输运，改变缺陷电荷状态的脉冲光，以及改变能级的压力。Higgins博士的团队在傅里叶变换朗道能级光谱方面具有优势。法国团队在异质结构中的磁输运和高压测量方面拥有专业知识，对异质结构的研究很有价值。本研究结果将：1)增加对半导体量子阱异质结构和量子尺寸效应器件的认识；2)为固体电子学的技术基础做出贡献。

This award will support cooperative research between Dr. Richard J. Higgins and his research group at Georgia Institute of Technology and Dr. J. C. Portal, Laboratoire de Physique des Solides, Institut National des Sciences Appliquees, Toulouse, France. Drs. Higgins and Portal will study the electronic and optoelectronic properties of 3-5 compound semiconductor heterostructures. The research will emphasize coherent (quantum) electronic effects, and identify growth and processing issues that inhibit quantum electronic devices. Two test systems will be studied: (a) coupled quantum well structures grown by molecular beam epitaxy, whose negative differential resistance promises sub-picosecond switching, but whose application is hampered by poor understanding of the physical behavior and (b) nanometer-scale structures patterned by e-beam lithography which can exhibit phase-coherent ballistic transport. Both the U.S. and French investigators have an active collaboration with shared research objectives in heterostructure magnetotransport. Techniques include magnetotransport to probe electronic behavior, pulsed light to alter defect charge state, and pressure to shift energy levels. Dr. Higgins' group brings strengths in Fourier Transform Landau Level spectroscopy. The French group has expertise in magnetotransport in heterostructures and also in high pressure measurements, valuable for heterostructure studies. The results of this research will: 1) increase understanding of semiconductor quantum-well heterostructure and quantum-size effect devices; and 2) contribute to the technology base of solid state electronics.