Multimode Emissions from MEH-PPV Blended with Polystyrene Film Waveguides

In the context of conjugated polymers, especially those of the poly (phenylenevinylene) (PPV) family, which are promising candidates as emission material in light emitting devices such as LEDs, field effect transistors and photovoltaic devices, we have, in the present study, prepared MEH-PPV [Poly [2- methoxy-5-(2’-ethyl-hexyloxy)-1,4-phenylen-evinylene] of low molecular weight and low polydispersity index. We discuss the thickness dependent fluorescence emission from the film waveguides fabricated with the above blends. Of the two peaks observed in this fluorescence spectrum, the shorter wavelength peak (562nm) is dominant in the range of lower thickness and as thickness is increased the longer wavelength peak (600nm) predominates. We also discuss the multimode laser emission from free standing MEH-PPV/Polystyrene film waveguides blends which show the nature of improvement in lasing behavior. The gain studies show that free standing film of MEH-PPV blended with Polystyrene can be used as a compact solid state laser.