Low loss contacts for organic semiconductor lasers

For the realization of electrically driven organic semiconductor lasers low loss contacts for charge injection are essential. The authors show that the addition of thin, highly transparent conducting layers (thickness on the order of 10-20 nm) of aluminum doped zinc oxide to a planar waveguide structure formed by a 145 nm thick polymer active layer leaves the threshold for the onset of amplified spontaneous emission almost unchanged. This finding paves the way towards electrically driven organic lasers without the need for unrealistically thick organic spacers to keep the waveguide mode away from the contacts. (c) 2006 American Institute of Physics.