Angle-independent narrowband emission is crucial for various optoelectronic applications. While materials like organics and perovskites offer electroluminescence, their broad emission spectra limit performance. Coupling emission to optical resonances narrows linewidth but introduces angular dispersion. This research presents a novel approach using an 'assistant strong coupling layer' in organic light-emitting diodes (OLEDs) to achieve highly efficient polariton-based emission. Red and green-emitting POLEDs with narrowband (<20 nm FWHM), spectrally tunable emission, up to 10% external quantum efficiency, and high luminance (>20,000 cd m⁻² at 5 V) were realized. Optimized cavity detuning and coupling strength yielded ultralow dispersion (<10 nm spectral shift at 60° tilt), enabling angle-independent emission suitable for display technology and other applications.

Andreas Mischok, Sabina Hillebrandt, Seonil Kwon, Malte C. Gather