Al_xGa_(1-x)As/Al_yGa_(1-y)As微腔中的激子吸收增强效应

ENHANCEMENT OF EXCITONIC ABSORPTION IN Al_xGa_(1-x)As/Al_yGa_(1-y),As MICROCAVITY

文章采用AlxGa1-xAs／AlyGa1-yAs微腔结构，研究了微腔中激子的吸收行为，在室温下观察到了激子吸收的增强效应，激子的峰值吸收强度是自由空间中激子吸收强度的2，6倍；我们从激子与光波场相互作用和腔中模函数的分布建立了计算．激子先吸收的模型，文中给出的微腔结构的数值计算表明激子的吸收增强与实验结果相一致；数值计算表明，微腔中激子吸收的强弱不仅与上、下两腔镜的反射率和腔长有关，而且还取决于量子阱在腔中的位置．

In this paper in A1x Ga1-x As / Aly Ga1-y. As micro -- cavity structure was grown for the investigation of optical absorption of excitons confined in quantum wells. The enhancement of exciton absorption was observed in the reflective spectroscopy. The peak absorption intensity of excitons in the micro -- cavity was 2. 6 times of the absorption of excitons in free space. A model of the interaction of excitons and optical wave interaction and mode function distribution is built to describe the enhancement. The calculation using the model shows the consistence of calculated enhancement of exciton absorption with the experimental result. The calculation also demonstrates that the strength of exction absorption in the micro -- cavity depends on the length, the reflectance of top and bottom mirrors,and the position of the quantum well sandwiched in the micro--cavity as well.