Optically pumped lasing of an electrically active hybrid OLED-microcavity

Abstract

Highly conductive electrodes are a prerequisite for electrically pumped organic lasers. We investigate the influence of very thin metal contacts in an electrically active organic microcavity. We test different deposition techniques and seed layers to decrease the thickness of the metal layers and reduce possibly harmful absorption. For such very thin contacts, the spectral position of the modes is modeled by simulated modes using the transfer-matrix-algorithm. The input-output characteristics of the device without, with bottom, with top, and with both metal layer(s) are recorded. These measurements allow us to understand and improve the impact on the functionality. With these results and the help of a theoretical approximation, we determine the minimal current density needed to reach the lasing threshold for electrical pumping in this sample structure.