Arkansas Institute of Nanoscale Materials Science and Engineering, University of Arkansas, Fayetteville, AR 72701, USA.
Nanoscale. 2011 Apr;3(4):1485-8. doi: 10.1039/c0nr00973c. Epub 2011 Mar 8.
The morphology and optical properties of In(0.35)Ga(0.65)As/GaAs quantum dots (QDs) grown on (210), (311)A, (711)A, (731) and (100) substrates are investigated. QDs formed on (210) and (731) oriented substrates are grown by molecular beam epitaxy. Regular QDs are observed on (100), (311)A, and (711)A. Randomly distributed QDs and comet-shaped QDs form on (210) and (731) substrates, respectively. A high density of QDs on the order of 10(11) cm(-2) are obtained from (711)A. The optical measurement shows a spectrum linewidth (FWHM = 74.3 nm) of QDs on GaAs (210) three times wider than GaAs (100) substrate. Long exciton decay times, over 1 ns, are also measured by time-resolved photoluminescence technique for all samples. Our results demonstrate the potential for QDs on GaAs high index substrates for wideband applications.
研究了在（210）、（311）A、（711）A、（731）和（100）衬底上生长的 In(0.35)Ga(0.65)As/GaAs 量子点（QD）的形态和光学性质。通过分子束外延法在（210）和（731）取向衬底上生长形成规则的 QD。在（100）、（311）A 和（711）A 上观察到随机分布的 QD 和彗形 QD。在（210）和（731）衬底上分别形成了高密度的 QD，密度约为 10(11) cm(-2)。光学测量表明，GaAs（210）上的 QD 光谱线宽（FWHM=74.3nm）比 GaAs（100）衬底宽三倍。通过时间分辨光致发光技术，还测量了所有样品的长激子衰减时间，超过 1ns。我们的结果表明，在 GaAs 高指数衬底上的 QD 具有宽带应用的潜力。
