Far-infrared Studies of Compound Semiconductors

这项建议描述了一项化合物半导体的远红外(FIR)磁谱研究计划，重点是II-VI化合物及其三元合金的层状结构，包括稀磁半导体(DMS)。将有四个方面的调查。首先，他们将利用FIR磁光技术研究分子束外延(MBE)和原子层外延(ALE)制备的宽禁带II-VI半导体化合物及其三元合金的掺杂外延层的杂质能级。重点将放在氢施主能级，其特征能量(1s-2p跃迁，电离能，DMS合金中的自旋分裂等)。对应于FIR能量范围。其次，他们建议将这些相同的技术应用于掺杂II-VI基超晶格和量子阱中的杂质的研究，其中杂质能级取决于量子井几何形状和杂质分布。第三，他们将使用FIR磁谱学来研究涉及窄禁带半导体的量子井、超晶格和界面。第四，他们将研究锰基稀磁半导体中的反铁磁共振，这样的研究可以提供关于动态自旋过程的明确信息。该计划的优点之一是，许多要研究的层状结构-以及大块样品-可以在他们自己的材料制备实验室中制备，要么通过分子束外延，要么通过传统的晶体生长技术(对于反铁磁共振研究的样品)。

This proposal describes a program of far-infrared (FIR) magnetospectroscopic studies of compound semiconductors, with strong emphasis on layered structures of II-VI compounds and their ternary alloys, including diluted magnetic semiconductors (DMS). There will be four areas of investigations. First, they will employ FIR magnetooptical techniques to study impurity levels of doped epilayers of wide gap II-VI semiconductor compounds and their ternary alloys prepared by molecular beam epitaxy (MBE) and by atomic layer epitaxy (ALE). The focus will be on hydrogenic donor levels, whose characteristic energies (1s - 2p transition, ionization energy, spin splitting in DMS alloys, etc.) correspond to the FIR energy range. Second, they propose to apply these same techniques to the study of impurities in doped II-VI based superlattices and quantum wells, where the impurity levels depend on the quantum well geometry and on impurity distribution. Third, they will use FIR magnetospectroscopy to study quantum wells, superlattices, and interfaces involving narrow gap semiconductors. Fourth, they will investigate antiferromagnetic resonance in manganese based diluted magnetic semiconductors, where such studies can provide definitive information on dynamical spin processes. One of the strengths of the proposed program is that many of the layered structures to be investigated - as well as bulk samples - can be prepared in their own materials preparation laboratory, either by MBE or (in the case of samples for the antiferromagnetic resonance studies) by conventional crystal growth techniques.