A hybrid state of light and material can significantly improve the brightness of the OLED

Researchers have developed a theoretical model that predicts a significant increase in the brightness of organic light emitting diodes (OLEDs) by exploiting a new quantum state called polytons. Integrating Polaritons into OLEDS requires effective discovery of new materials, making practical implementation an exciting challenge.

OLED technology has become a common light source for a variety of high-end display devices, including smartphones, laptops, TVs, and smartwatches.

OLEDs are rapidly reshaping lighting applications with flexibility and environmental friendliness, but they are very slow to convert currents into light, with only a 25% chance of ejecting photons efficiently and quickly . The latter is an important condition for increasing the brightness of OLEDs and tends to be dimier than other light technologies.

Researchers at the University of Turk in Finland and Cornell in the US have proposed predictive models to overcome this problem. Their research is published in Advanced Optical Materials.

OLEDs are electronic components made from organic carbon-based compounds that produce light when currents are applied. In OLED displays, the pixels themselves emit light, unlike LCDs that use LED backlights.

When sandwiched between two semi-transparent mirrors, the organic emitter can combine with the trapped light, creating a new hybrid state of matter, called a polyton.

By fine-tuning these conditions, you can find sweet spots where the remaining 75% dark state begins to turn into lighter polytons instead.

“The general idea of ​​using polaritons in OLED technology is not entirely original, but it lacks the theory of examining performance boundaries. This work involves exploring where polariton sweet spots are in various scenarios. I looked carefully.

“We found that the strength of the polaritonic effect on OLEDS performance depends on the number of molecules bound.

“The molecules we studied and single binding molecules have significantly improved efficiency. The dark to bright conversion rate has increased by 10 million times at most,” says postdoctoral researcher Oli Siltanen.

Polalitonic effects could be negligible for many molecules. Therefore, the current dark to bright conversion speed of OLEDs cannot be enhanced simply by equipping a mirror.

“The next challenge is to develop a viable architecture that promotes the strong binding of single molecules. We invent new molecules tailored to polariton OLEDS. Both approaches are challenging, but As a result, the efficiency and brightness of OLED displays can be significantly improved.

The widespread adoption of OLEDs is hampered by efficiency, but more importantly, brightness restrictions, especially when compared to traditional inorganic LEDs. The results of this study not only provide a path forward to laying the foundations and allowing OLEDs to achieve performance levels that were previously considered impossible, as well as providing a path forward.