Periodically-pumped organic microlasers

在这个项目中，我们提出的实验和理论研究的局部准模和形成的超模在平面微腔具有有机活性介质。为此，平面有机微腔将以空间非均匀的方式被激发，以引起有机腔层内的增益和吸收分布的空间调制。本文的主要工作将放在利用干涉图样对有机微腔进行周期性光泵浦的实验上。在这种情况下，我们的相干性的结果表明，可以在整个泵模式的平面内延伸，不再受到限制的微腔，这是相互的平面结构，通常是非常小的模式体积。这一观察对于未来的应用至关重要，这将涉及有机微腔激光器的周期性电泵浦。 首先，它表明，由于相干性的面内传播，激光体积可能会扩大，这可能会导致单模有机激光器的发射功率更高。其次，由于面内矢量的离散化导致相对于反射镜的法线的倾斜发射，使得相干光的传播矢量不再与电流流动一致。这种解耦的光流从电激励减少的接触和电流的影响，这是寄生的，降低激光器的性能和characteristics.The项目的目的是获得一个基本的了解，在平面微腔空间相干过程，并开发操作这些过程的能力。与将不同结构直接结合到腔层中或甚至该层的物理结构化相比，使用周期性光泵浦在实验中提供了无与伦比的灵活性。它既可以优化这些结构，用于将来加入例如金属接触，也可以更深入地了解微腔激光器的基本物理特性。

In this project, we propose the experimental and theoretical investigation of localised quasimodes and the formation of supermodes in planar microcavities having an organic active medium. To this end, the planar organic microcavities shall be excited in a spatially inhomogeneous fashion, to induce a spatial modulation of the distributions of gain and absorption within the organic cavity layer. A major effort will be put on the experiments which use an interference patterns for periodic optical pumping of organic microcavities. In this case, our preliminar results show that the coherence may extend in-plane over the entire pump pattern and is not restricted anymore by the mode volume of the microcavity, which is mutual to the planar structures and is typically very small. This observation is of crucial importance for the future applications which will involve a periodic electrical pumping of organic microcavity lasers. First of all it shows, that the lasing volume may be extended due to the in-plane propagation of the coherence, which might lead to much higher emission powers of a single-mode organic laser. Secondly, since discretization of the in-plane vector leads to an oblique emission with respect to the normal of mirrors, so that the propagation vector for the coherent light does not concide anymore with the electric current flow. This decoupling of the optical flow from the electrical excitation reduces the influence of the contacts and currents, which are parasitic and degrade laser performance and characteristics.The aim of the project is to obtain a basic understanding of spatially coherent processes in a planar microcavity, and to develop the ability to manipulate these processes. In contrast to the direct incorporation of different structures into the cavity layer or even physical structuring of this layer, the use of the periodic optical pumping offers an incomparable flexibility in the experiments. It allows both to optimize these structures for the future incorporation of e.g. metal contacts and also to obtain a deeper understanding of the fundamental physics of microcavity lasers.