Heyn Ch, Klingbeil M, Strelow Ch, Stemmann A, Mendach S, Hansen W
Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Jungiusstraße 11, D-20355 Hamburg, Germany.
Nanoscale Res Lett. 2010 Jul 14;5(10):1633-6. doi: 10.1007/s11671-010-9687-x.
We study the optical emission of single GaAs quantum dots (QDs). The QDs are fabricated by filling of nanoholes in AlGaAs and AlAs which are generated in a self-assembled fashion by local droplet etching with Al droplets. Using suitable process parameters, we create either uniform QDs in partially filled deep holes or QDs with very broad size distribution in completely filled shallow holes. Micro photoluminescence measurements of single QDs of both types establish sharp excitonic peaks. We measure a fine-structure splitting in the range of 22-40μeV and no dependence on QD size. Furthermore, we find a decrease in exciton-biexciton splitting with increasing QD size.
我们研究了单个砷化镓量子点(QD)的光发射。这些量子点是通过填充铝镓砷和砷化铝中的纳米孔制造而成,这些纳米孔是通过用铝液滴进行局部液滴蚀刻以自组装方式生成的。通过使用合适的工艺参数,我们在部分填充的深孔中制造出均匀的量子点,或者在完全填充的浅孔中制造出尺寸分布非常宽的量子点。对这两种类型的单个量子点进行的微光致发光测量都确定了尖锐的激子峰。我们测量到精细结构分裂在22 - 40微电子伏特范围内,并且不依赖于量子点尺寸。此外,我们发现随着量子点尺寸的增加,激子 - 双激子分裂减小。