LAUSR

Abstract Reaching high current densities is an essential need to achieve electrically driven organic semiconductor lasers (OSLs). This requires highly conductive (usually metallic) electrodes which on the other hand cause unwanted optical losses. Here, we introduce a concept for organic light-emitting diodes (OLEDs) where the layer sequence is restructured in order to concentrate and maximize the current flow in a metal-free area. Thus, we do not only avoid parasitic absorption by the metal electrodes, but also drastically reduce the power dissipation. These devices enable higher current densities than the standard OLED design due to reduced self-heating as a consequence of an active area which automatically shrinks down to an appropriate size. They further allow for integration into an organic microcavity. Therefore, the new concept is well suited to realize an electrically driven OSL in future.