Towards OCPLEDs: Organic Circularly Polarised Light Emitting Devices

有机发光二极管（oled）需要一个位于两个电极之间的有机半导体材料的发射电致发光层，其中至少一个电极是透明的。这种设备正在革新显示技术，使柔性和全透明设备的生产成为可能。发射圆偏振电致发光（CPEL）的设备应该在光子技术中具有巨大的转化潜力，例如高度改进的LCD背光，彩色图像检测和立体显示，光通信和量子计算，但是迄今为止直接产生CPEL的问题尚未解决。本研究的目的是利用固有手性、导电和发光的小分子作为oled中的电致发光层，试图证明高效的CPEL。这种工作将对现有知识产生重大影响，可在若干转化领域加以利用。以替代LCD背光为例，目前的技术依赖于偏振滤光片，可以有效地切断这些显示器中使用的75%的光。结合滤色器和设备接口的吸收，只有4%的光被透射出去。偏振光源的使用，加上可调谐的颜色组件，将消除这种需求，从而导致更节能的显示器，显著降低碳足迹。

Organic light emitting diodes (OLEDs) require an emissive electroluminescent layer of an organic semiconductor material located between two electrodes, where at least one of the electrodes is transparent. Such devices are revolutionising display technologies, with the production of flexible and fully transparent devices possible. Devices that emit circularly polarised electroluminescence (CPEL) should have vast translational potential in photonic technology, such as highly improved LCD backlighting, colour-image detection and stereoscopic displays, optical communication, and quantum computing, however to date the problem of directly generating CPEL has not been solved. The goal of this research is to use intrinsically chiral, conductive and luminescent small molecules as electroluminescent layer in OLEDs, in an attempt to demonstrate efficient CPEL. Such work would have significant impact on current knowledge, which could be exploited in a number of translational areas. Taking alternative LCD backlighting as one example of the exploitation of this work, current technologies rely on polarising filters that effectively cut out 75% of the light used in these displays. Combined with absorption by the colour filters and at device interfaces, only 4% of the light used is transmitted. The use of a polarised light source, coupled with tuneable colour components would remove this need, thus leading to significantly more energy efficient displays, with a dramatically lowered carbon footprint.