During the last two decades, organic semiconductor lasers (OSLs) have been attracted much attention due to their advantageous properties such as wavelength tunability in visible range , low cost, flexibility and large area fabrication . These properties make them good candidates for a range of applications including sensing, spectroscopy and optical communication. However, only optically pumped organic lasers have been realized so far and the demonstration of an electrically-driven organic laser diode still remains a very challenging task. To achieve electrically pumped OSLs, much effort has been focused on the reduction of the energy threshold of optically pumped organic lasers by enhancing the gain media properties and optimizing the resonant cavities. The injection of high current density involves Joule heating which causes degradation and breakdown of the device. Moreover, the presence of high charge density induces multiple annihilation processes such as exciton-polaron quenching, polaron absorption and electric field dissociation which are ones of the causes of device external quantum efficiency rolloff. A fundamental understanding of the physical mechanisms governing the device operation is crucial to optimize the device performance and overcome the limitation processes to the achievement of an electrically driven OSLs. Electrical simulation of an organic light emitting diode under high current density is performed in order to predict the current at high voltage. The influence of the various annihilation processes is investigated by solving the exciton continuity equation.
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