Probing polariton condensation dynamics by multiquantum coherent spectroscopy in organic optical microcavities

通过有机光学微腔中的多量子相干光谱探测极化子凝聚动力学

• 批准号: 422383-2012
• 负责人: Silva, Carlos
• 金额: $ 10.91万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=495782
• 关键词: Probing; polariton; condensation; dynamics; multiquantum

The prospect of 'plastic' lasers, in which each component is composed of polymers or molecules, is exciting because these can be processed simply from solution, reducing significantly their cost of fabrication, and because the flexibility of plastics presents opportunities to conceive flexible lasers. Furthermore, the optical properties of each component can be tuned synthetically; these materials can be designed to emit light very efficiently in the red, green or blue regions of the visible spectrum. However, implementing commercially viable plastic lasers presents many challenges, primarily because excited states of these materials absorb light strongly at wavelengths close to the emission wavelength, and thus high excited-state densities are necessary to induce laser effects. However, a promising alternative approach has been proposed and demonstrated using traditional semiconductors, so-called polariton lasers. These devices exploit the strong interaction of light and electrons, in which new quasi-particles that can be considered to be part photons and part electrons, are generated. These quasi-particles are termed polaritons, and they have the very special property that are so-called bosons. Practically, this means that two or more polaritons may occupy the same quantum-mechanical state. If the boson density is high enough, a large fraction of these occupy the lowest quantum state, at which point quantum effects (coherence; like a large ensemble of cooperative skater pairs all performing in exquisite choreography when the spotlight is upon them) become apparent spontaneously on a macroscopic scale, i.e., the polariton wavefunctions overlap spatially over large lengthscales. The strong photonic character of polaritons permits such coherence to an extent that is challenging for excitons (excited electrons), which are 'dirty' bosons and undergo mutual annihilation at high density. Spontaneous coherence is at the origin lasing in polariton lasers: the optical leakage of out of the spontaneously coherence state is the source of laser light. In this project, we will develop an experimental apparatus that will probe with unprecedented detail the interactions between polaritons that give rise to spontaneous coherence.

每个组件由聚合物或分子组成的“塑料”激光器的前景令人兴奋，因为这些激光器可以简单地从溶液中处理，从而大大降低了它们的制造成本，并且塑料的柔韧性带来了构思柔性激光器的机会。此外，每个组件的光学特性都可以合成。这些材料可以设计为在可见光谱的红色，绿色或蓝色区域中非常有效地发光。但是，实施商业上可行的塑料激光器提出了许多挑战，主要是因为这些材料的激发态在接近发射波长的波长下强烈吸收光，因此需要高激发态密度来诱导激光效应。然而，已经提出了一种有希望的替代方法，并使用传统的半导体，所谓的polariton激光器进行了证明。这些设备利用了光与电子的强相互作用，其中可以产生可以认为是部分光子和部分电子的新的准粒子。这些准粒子被称为polariton，它们具有所谓的玻色子的特殊特性。实际上，这意味着两个或多个极性子可能占据相同的量子机械状态。如果玻色子密度足够高，那么其中很大一部分占量子状态的最低状态，在此点量子效应（相干；就像大量合作的滑冰运动员配对时，当众人瞩目的聚光灯下方时，它们都会在宏观的尺度上自发地自发地发挥作用。极化子的强光子特征允许这种连贯性在某种程度上对激发剂（激发电子）具有挑战性，后者是“脏”玻色子，并在高密度下进行相互歼灭。自发的连贯性在极化激光器中的起源激光：从自发相干状态中的光学泄漏是激光的来源。在这个项目中，我们将开发一个实验设备，该设备将以前所未有的细节进行探测，从而导致自发连贯性的极化子之间的相互作用。