High-field studies of the band dispersion in novel semiconductor materials: Dilute nitride semiconductors and Ge/SiGe quantum wells

在第一部分中，本项目旨在系统研究氮浓度对InAs1-xNx、GaAs1-xNx和InSb1-xNx有效质量的影响，这对于理解氮掺入导致的导电带结构改变的基本原理至关重要。最直接的实验，高场回旋共振（CR）吸收，将在广泛的激发波长和温度范围内对不同氮含量的样品进行。CR测量将通过其他常见的间接方法完成，包括红外反射率和磁光致发光研究，以了解文献中发表的高度分散的有效质量值的起源。在第二部分中，重点讨论了Ge/SiGe异质结构，由于锗具有更高的固有载流子迁移率，因此在下一代高速电子器件中，Ge/SiGe异质结构有望取代Si/SiGe系统。在宽激发波长范围内，利用高场CR研究双轴应变对空穴有效质量和价带能色散的影响。

In the first part, the project aims to systematically study the effect of nitrogen concentration on the effective mass of InAs1-xNx, GaAs1-xNx, and InSb1-xNx, which is of key importance for understanding the fundamentals of the conduction bandstructure modification due to the incorporation of nitrogen. The most direct experiment, high field cyclotron resonance (CR) absorption, will be performed on sets of samples with various nitrogen content under wide range of excitation wavelengths and temperatures. The CR measurements will be completed with other common indirect methods, including infrared 3 reflectivity and magneto-photoluminescence studies in order to understand the origin of the highly dispersed values of the effective mass published in the literature.In the second part, the attention is addressed to Ge/SiGe heterostructures, which are promising candidates to replace Si/SiGe systems in the next generation of high speed electronics, due to higher intrinsic carrier mobility in Germanium. The effect of biaxial strain on the hole effective mass and the valence band energy dispersion will be studied using high field CR under wide range of excitation wavelength.