Surface plasmon enhanced blue organic light emitting diode with nearly 100% fluorescence efficiency

Surface plasmon (SP) enhanced blue organic light emitting diodes (OLEDs) have been realized by using silver nanoclusters (SNCs) deposited using thermal evaporation technique. SNCs were found to have the surface plasmon resonance at wavelength 445 nm and were used with blue emitting layer BCzVBi. The optimized OLED (in terms of the size of SNCs and the distance between SNCs and emitting layer) were found to have the efficiency two times higher than reference OLED without SNCs. Internal quantum efficiency was calculated to be 24% for SP enhanced OLED owing to 96% fluorescence efficiency. Energy transfer between exciton and SPs with the separation distance have been studied experimentally and using 2D-FDTD simulation and surface–dipole energy transfer has been observed.