The Influence of Excited State Physics in Conjugated Polymer Devices

在过去的十年里，在用柔性塑料材料制造显示器、照明电池板、太阳能电池和激光方面取得了显著的进步。这具有广泛的潜在应用，例如卷起电视显示屏或将发电、传感器和数据通信系统编织到您的衣服中。有机LED技术现在已经成熟到OLED显示屏在手机等消费产品中大规模生产的程度。下一代塑料电子产品将包括OLED照明、太阳能电池和激光。然而，现在很清楚的是，为了为这些要求苛刻的应用提供技术，有必要对基础材料物理学有更深的理解。在所有这些装置中，分子激发态的物理特性对性能起着至关重要的作用。在OLED中，高亮度下的效率受到电荷载流子吸收和各种相互作用的限制，这些相互作用抑制了激发态的光发射。在激光中，激发态物理和激光损耗之间存在着微妙的相互作用，到目前为止，人们对如何利用材料的化学和结构特性来控制这一点知之甚少。这项建议旨在通过汇集两个小组的专业知识来发展这种理解：一个小组是测量这些聚合物的光电性能和它们在光子学中的应用方面的专家，另一个小组是有机材料量子理论的专家。通过理论和实验的结合，我们将致力于了解有机半导体的复杂激发态相互作用，并发现控制这些过程的新的设计策略。这将帮助我们优化现有设备的性能(例如，效率和亮度)；并使基于这些材料的新一代光子设备成为可能。我们将对材料中的基本激发态过程及其在器件条件下的行为进行光学测量。利用量子力学中最先进的技术，我们还可以模拟产生这些效应的微观物理。测量工作设备中的这些相互作用要求特别高，为了实现这一点，我们还将利用我们在剑桥显示技术公司和阿利坎特大学的项目合作伙伴的具体补充专业知识。然后，我们将把我们关于激发态的新知识应用到一系列有机设备的操作中，包括有机发光二极管、激光、太阳能电池和光学放大器。我们将量化不同激发态相互作用的重要性，并开发能够最小化寄生过程和优化操作的设计策略。

There has been remarkable progress over the last decade in making displays, lighting panels, solar cells and lasers out of flexible, plastic materials. This has a wide range of potential applications, such as roll up TV displays or having power generation, sensors and data communications systems woven into your clothing. The technology of organic LEDs has now matured to the degree that OLED displays are mass produced in consumer products such as mobile phones. The next generations of plastic electronics products will include OLED lighting, solar cells and lasers. It is now clear however that to deliver the technology for these demanding applications it is necessary to develop a deeper understanding of the basic materials physics. In all of these devices the physics of the excited states of molecules plays a crucial role in performance. In OLEDs the efficiency at high brightness is limited by the absorption due to charge carriers and various interactions that quench the light emission from excited states. In lasers there is a delicate interplay of the excited state physics and laser losses, and so far little is known about how the chemical and structural properties of the materials may be used to control this. This proposal seeks to develop this understanding by bringing together the expertise of two groups: one who are experts in measuring the optoelectronic performance of these polymers and in their application for photonics, and the other who are experts in the quantum theory of organic materials. Through a combination of theory and experiment we will aim to understand the complex excited state interactions of organic semiconductors, and uncover new design strategies to control these processes. This would help us to optimise the performance (e.g. efficiency and brightness) of current devices; and enable new generations of photonic devices based on these materials. We will make optical measurements of the fundamental excited-state processes in the materials and their behaviour under device conditions. Using state-of-the-art techniques in quantum mechanics we can also simulate the microscopic physics which gives rise to these effects. Measuring these interactions in working devices is particularly demanding and to achieve this we will also draw on specific complementary expertise from our project partners at Cambridge Display Technologies and the University of Alicante. We will then apply our new knowledge of excited states to the operation of a range of organic devices including OLEDs, lasers, solar cells and optical amplifiers. We will quantify the significance of the different excited state interactions and develop design strategies that can minimise parasitic processes and optimise operation.