Faraday-Stark Optoelectronic Effect

9623248海曼这个提议的目的是研究量子井结构中基于法拉第旋转的一种新的光电效应。初步工作表明，外加电压可以用来控制法拉第旋转度。这种效应是新颖的，因为旋转度是由电场而不是磁场控制的。这可能导致对光开关和宽带光调制器的电子控制。基于法拉第-斯塔克效应的光电子器件只需要一个低的开关电压(~伏)和一个由永磁体提供的小的直流磁场(L特斯拉)。光学调制器的一些独特功能包括：*高带宽光调制，10^10赫兹；*关机状态下的极低透射率，10^-5；以及40分贝调制深度；*与微光刻和波导兼容。关于Faraday-Stark效应的初步实验是在加州大学圣巴巴拉分校(A.C.Gossard组)生长的GaAs量子阱样品上进行的。虽然这种结构没有针对法拉第-斯塔克效应进行优化，但麻省理工学院电气工程系(C.Fonstad组)正在培育改进的结构。对于室温器件来说，特别重要的是由II-VI磁性半导体结构制成的结构。这些材料将在我们自己的分子束外延机中生长，这台机器是由NSF工程研究拨款和AT&amp；T的种子资金制造的。我们将使用磁光实验来研究各种II-VI和III-V材料结构。这些结果将有助于研究设计工作在感兴趣的波长的设备的可能性。我们的目标是确定光电光开关、调制器和电控光隔离器所需的限制和最佳条件。该研究项目将为学生提供工程、物理和材料科学方面的广泛教育。它还提供许多领域的实践培训，包括光学、磁学、半导体、分子束外延晶体生长、微制造、低维科学、高速电子、低温和高场磁体。这种基础广泛的教育很可能会对研究生和本科生未来的就业产生影响。此外，光学领域的教育非常有价值，因为就业市场通常会超过合格毕业生的数量。***

9623248 Heiman The aim of this proposal is to investigate a new optoelectronic effect based on Faraday rotation in quantum well structures. Preliminary work has demonstrated that an applied voltage can be used to control the degree of Faraday rotation. This effect is novel in the sense that the degree of rotation is controlled by an electric field as opposed to a magnetic field. This could lead to electronic control of light switches and wide bandwidth optical modulators. Optoelectronic devices based on the Faraday-Stark effect would require only a low switching voltage (~ volt) and a small dc magnetic field ( l tesla) supplied by a permanent magnet. Some unique features for optical modulators include: * high-bandwidth light modulation, 10^10 Hz; * very low transmission in the off-state, 10^-5; and 40 dB modulation depth; * compatibility with microlithography and waveguides. Initial experiments on the Faraday-Stark effect were performed on a GaAs quantum well sample grown at UC Santa Barbara (group of A.C. Gossard). Although this structure was not optimized for the Faraday-Stark effect, improved structures are being grown in the Electrical Engineering Department at MIT (group of C. Fonstad). Of particular importance for room temperature devices are structures made from II-VI magnetic semiconductor structures. These will be grown in our own MBE machine, which was fabricated with funding from an NSF Engineering Research Grant and seed funding from AT&T. A variety of II-VI and III-V material structures will be investigated using magneto-optical experiments. These results will be helpful in examining the possibilities for designing devices that operate at wavelengths of interest. Our ambition is to determine the limitations and optimum conditions required for optoelectronic light switches, modulators, and electrically-controlled optical isolators. This research program will provide students with a broad education in engineering, physics, and materi als science. It also provides hands-on training in many areas including optics, magnetism, semiconductors, MBE crystal growth, microfabrication, low-dimensional science, high-speed electronics, cryogenics, and high-field magnets. Such a broad-based education is likely to impact on the future employment of both graduate and undergraduate students. In addition, an education in the field of optics is exceptionally valuable since that job market usually exceeds the number of qualified graduates. ***