Light Emitting Field-Effect Transistors: A Route to Injection Lasing in Organic Materials

有机半导体结合了新颖的光电特性，简单的制造和调整化学结构以提供所需特征的范围，使其成为几乎每个经济和工业部门应用的有吸引力的候选者。有机染料激光器（光泵浦）目前用于通信和医疗应用，因为它们的颜色很容易调节，而且成本低。然而，由于有机材料的固有限制（电荷传输差和亮度猝灭），这些激光器中使用的有机染料不能被电抽运，这仍然是研究人员获得更好的材料，加工方法和器件架构的主要挑战。该项目解决了以下方面的研究挑战：1)实现新型发光场效应晶体管（LEFET）的高性能材料组合和器件结构，消除任何低效率；2)开发高速光电器件；3)为合适的低损耗光反馈结构创造高于激光阈值的高电流密度和激子密度。电泵固态有机激光器是一项极具吸引力的技术，因为它们具有相对容易实现颜色的潜力，这是无机激光器难以实现的，这将允许在通信，生物传感器和显示方面改进和创造广泛的新应用。

Organic semiconductors combine novel optoelectronic properties, with simple fabrication and the scope for tuning the chemical structure to give desired features, making them attractive candidates for the applications in almost every economic and industrial sector. Organic dye-lasers (optically pumped) are currently used in communication and medical applications because their colour can be easily tuned, and they are low-cost. However, the organic dyes used in these lasers cannot be electrically pumped because of the intrinsic limitations (poor charge transport and luminance quenching) of the organic materials, which remains a major challenge for the researchers to achieve better materials, processing methods and device architectures. This project addresses the research challenges in i) achieving high performance material combinations and device structures of novel light-emitting field-effect transistor (LEFET) that eliminate any inefficiencies for, ii) developing high speed optoelectronic devices and (iii) the creation of high current density and exciton densities above lasing threshold for suitable low-loss optical feedback structures. Electrically pumped solid-state organic lasers are highly attractive technology due to their potential in achieving colours at a relative ease, that are difficult to realise with inorganic lasers, and this will allow the improvement and creation of a wide range of new applications in communications, biomdecial sensors and displays.