Ulrich S M, Gies C, Ates S, Wiersig J, Reitzenstein S, Hofmann C, Löffler A, Forchel A, Jahnke F, Michler P
Institut für Strahlenphysik, Universität Stuttgart, Germany.
Phys Rev Lett. 2007 Jan 26;98(4):043906. doi: 10.1103/PhysRevLett.98.043906. Epub 2007 Jan 25.
We present measurements of first- and second-order coherence of quantum-dot micropillar lasers together with a semiconductor laser theory. Our results show a broad threshold region for the observed high-beta microcavities. The intensity jump is accompanied by both pronounced photon intensity fluctuations and strong coherence length changes. The investigations clearly visualize a smooth transition from spontaneous to predominantly stimulated emission which becomes harder to determine for high beta. In our theory, a microscopic approach is used to incorporate the semiconductor nature of quantum dots. The results are in agreement with the experimental intensity traces and the photon statistics measurements.
我们展示了量子点微柱激光器的一阶和二阶相干性测量结果，并结合了半导体激光理论。我们的结果表明，对于所观察到的高β微腔存在一个较宽的阈值区域。强度跃变伴随着明显的光子强度波动和强烈的相干长度变化。这些研究清楚地显示了从自发发射到主要受激发射的平滑过渡，而对于高β值来说，这种过渡变得更难确定。在我们的理论中，采用微观方法来纳入量子点的半导体特性。结果与实验强度轨迹和光子统计测量结果一致。
