Department of Physics, University of Arkansas, Fayetteville, AR 72701, USA.
Nanotechnology. 2011 Sep 16;22(37):375703. doi: 10.1088/0957-4484/22/37/375703. Epub 2011 Aug 19.
A Ga(AsBi) quantum well (QW) with Bi content reaching 6% and well width of 11 nm embedded in GaAs is grown by molecular beam epitaxy at low temperature and studied by means of high-resolution x-ray diffraction, photoluminescence (PL), and time-resolved PL. It is shown that for this growth regime, the QW is coherently strained to the substrate with a low dislocation density. The low temperature PL demonstrates a comparatively narrow excitonic linewidth of ∼ 40 meV. For high excitation density distinct QW excited states evolve in the emission spectra. The origins of peculiar PL dependences on temperature and excitation density are interpreted in terms of intra-well optical transitions.
低温下通过分子束外延生长了一个掺铋量达到 6%、阱宽为 11nm 的 Ga(AsBi)量子阱，并用高分辨率 X 射线衍射、光致发光（PL）和时间分辨 PL 进行了研究。结果表明，在这种生长条件下，量子阱与衬底具有较低的位错密度的完全应变。低温 PL 显示出约 40meV 的较窄的激子线宽。在高激发密度下，发射光谱中出现了明显的量子阱激发态。从阱内光学跃迁的角度解释了 PL 对温度和激发密度的特殊依赖关系的起源。
