Efficiency Analysis of Perovskite LEDs Via Optoelectronic Modeling

Perovskite light-emitting diodes (P-LEDs) are emerging candidates for efficient lighting and display applications, but their external quantum efficiency is limited by photon trapping and non-ideal recombination. In this work, we introduce an optoelectronic modeling approach that simultaneously accounts for carrier transport, recombination, and optical outcoupling through multiple dipole sources distributed according to the spontaneous emission profile. This method enables the consistent evaluation of both internal quantum efficiency and light extraction efficiency functions of perovskite thickness and applied bias. The results reveal a thickness-dependent trade-off: thinner layers favor higher light extraction efficiency (up to η LE ~15% at 36 nm). Whereas, thicker layers support larger internal quantum efficiency (up to η IQE ~ 59.8%). Notably, the maximum internal quantum efficiency (ηIQE) typically occurs near the diode turn-on voltage (VTO), which increases with the thickness of the perovskite, shifting to a bias where both internal and external quantum efficiencies reach their peak. Consequently, the external quantum efficiency reaches η EQE ~ 9.0% at 36 nm and VTO ~ 2.34 V, while the absolute maximum of η EQE ~9.46% appears for a 51-nm thick perovskite layer and VTO ~ 2.5 V. These findings highlight the necessity of considering electronic and optical effects, providing realistic guidance for optimizing P-LED performance. In particular, they indicate that a careful choice of the perovskite layer thickness alone can substantially enhance device efficiency, even before pursuing more complex optimization strategies.