半导体微结构物理效应及其应用讲座第三讲半导体的激子效应及其在光电子器件中的应用

人们对半导体中的电子空穴对在库仑互作用下形成的激子态及其有关的物理性质进行了深入研究.激子效应对半导体中的光吸收、发光、激射和光学非线性作用等物理过程具有重要影响,并在半导体光电子器件的研究和开发中得到了重要的应用.与半导体体材料相比,在量子化的低维电子结构中,激子的束缚能要大得多,激子效应增强,而且在较高温度或在电场作用下更稳定.这对制作利用激子效应的光电子器件非常有利.近年来量子阱、量子点等低维结构研究获得飞速的进展,已大大促进了激子效应在新型半导体光源和半导体非线性光电子器件领域的应用.

Excitonic effects in semiconductors and their applications in opto-electronic devices

The excitons in semiconductors formed by electron-hole pairs bound by Coulombic interaction have been well investigated. The excitonic effects have a great influence on physical processes such as optical absorption, luminescence, lasing, and optical non-linearity, and have significant applications in semiconductor opto-electronic devices. In quantized electronic low-dimensional structures the excitons have much larger binding energies than in bulk materials, showing stronger excitonic effects and being more stable at high temperatures or under high electric field conditions. They are very beneficial to the fabrication of opto-electronic devices with improved performance. The progress obtained recently in investigations on quantum wells,quantum dots and other low-dimensional structures have greatly promoted the applications of excitonic effects in many new semiconductor light sources and non-linear opto-electronic devices.