微型量子点激光器理论研究

发布时间：2018-12-26 07:19

【摘要】：基于量子点-微腔系统的微型激光器由于其优秀的特性,一直受到研究人员的广泛关注。通过研究微型量子点激光器的泵浦方式、光谱学和激射性能,很多有价值的发现涌现出来,这些结果让人们更好的了解了光和物质之间的作用原理,打开了人们探索量子世界的大门。在众多关于量子点激光器的研究中,对系统所施加的泵浦要不然选择的是相干泵浦,要不然就是非相干泵浦。很少有研究将二者统一起来,并探讨相应的激射性能提高的可能性。本文创造性地将这两种泵浦方式结合起来,在此框架上进行分析,探讨了其可能性。我们采用了全量子理论和Jaynes-Cummings模型,并根据不同的初始条件,对相应的系统的薛定谔方程(即量子主方程)进行了修正,并对方程进行了求解并进行了仿真。仿真结果表明,相对于其他方案,我们的方案可以更好地实现量子点微腔系统的激射性能。具体来说,在非相干泵浦条件下,提高量子点激光器的性能可以采用两种新的途径,即采用匹配条件或者引入相干泵浦。匹配条件的应用,则可以使强耦合的范围最大化,从而实现改善系统性能的作用。而通过引入相干泵浦,并调节强度,我们可以将光子的统计分布调节到泊松分布,同样可以获得相干性好的激光。采用匹配条件对量子点激光器的制备工艺提出了更加严格的要求,而泵浦结合的方案则更容易实现。除此之外,我们还具体对相干泵浦和非相干泵浦各自作用于系统的光谱进行了分析。从光谱中,我们发现随着泵浦强度的增加,系统会逐渐从量子区域转向激射区域。对两种泵浦共同激发系统的方案,光谱则更加的复杂,但同样可以观察到类似的现象。
[Abstract]:The micro laser based on quantum dot-microcavity system has been paid more and more attention because of its excellent properties. Many valuable discoveries have emerged by studying the pumping methods, spectroscopy, and emission performance of miniature quantum dot lasers, which have given people a better understanding of the mechanism of the interaction between light and matter. Opened the door for people to explore the quantum world. In many researches on quantum dot laser, the pump applied to the system is either coherent pump or incoherent pump. There are few studies to unify the two and to explore the possibility of improving the corresponding emission performance. In this paper, we creatively combine these two pumping methods, and analyze them on this frame, and discuss the possibility of them. We adopt the full quantum theory and Jaynes-Cummings model, and according to different initial conditions, we modify the Schrodinger equation (the quantum master equation) of the corresponding system, and solve the equation and simulate it. The simulation results show that compared with other schemes, our scheme can better achieve the lasing performance of quantum dot microcavity system. In particular, there are two new ways to improve the performance of quantum dot laser under the condition of incoherent pumping, that is, using matching condition or introducing coherent pumping. The application of matching condition can maximize the range of strong coupling and improve the system performance. By introducing coherent pump and adjusting the intensity, we can adjust the statistical distribution of photons to Poisson distribution, and we can also obtain good coherence laser. The matching condition is used to make the quantum dot laser more strict, and the pump combination scheme is easier to realize. In addition, we analyze the spectrum of coherent pump and incoherent pump respectively. From the spectrum we find that with the increase of pumping intensity the system will gradually change from the quantum region to the stimulated region. For the two pumping co-excitation systems, the spectrum is more complex, but similar phenomena can also be observed.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN248

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