CONTROL OF PHOTOLUMINESCENCE EMISSION FROM A CONJUGATED POLYMER USINGAN OPTIMIZED MICROCAVITY STRUCTURE

It is shown that by careful control of the position of a thin emissive polymer layer {poly(p-phenylene vinylene) [PPV]} within a microcavity structure, it is possible to strongly influence the forward photolumi nescence (PL) emission intensity. In one structure, the PPV layer was placed at a confined photon-field antinode where the coupling strength between the emitting dipoles and the field is expected to be a maximu m. This resulted in an enhancement of the PL emitted into the forward direction. Placing the PPV layer at a photon-field node resulted in st rong suppression of PL. The ratio of the forward emission intensity be tween these two extreme cases was 55 +/- 25. The measured emission int ensities are compared to predictions from a transfer matrix model and are shown to be in very reasonable agreement.