We report here the synthesis of ZnO films by the pulsed-laser deposition technique using various novel conditions. The
dopants are As, Ga, Al and N. The films show excellent crystalline quality with atomically smooth surface morphology.
The electrical resistivity was found to be close to 2 x~10-4 ohm-cm and transmittance >85% with both Ga and Al doping.
Doping with As shows several distinct transitions in their electrical resistivity and strong aging effects. On the other
hand, doping with Mn in ZnO reduces the grain size. On the other hand, doping with trivalent Er ions in ZnO films
causes two effects: for high doping (>8 wt%), a substantial enhancement of diagonal piezo-optic effect (up to 3.7*10-13
m2/N at &lgr;=633 nm) was observed due to creation of additional dipole moments at the interface of the film and the
substrate, and higher electrical conductivity with enhanced 1.54 &mgr;m emission was demonstrated at room temperature for
low concentration (<2 wt%) of Er. Furthermore, no quenching effects in emission characteristics at 1.54 &mgr;m were
observed up to 2 wt % of Er-doping in ZnO at room-temperature.
The optical properties of previously synthesized sulfone and methoxy substituted block co-polymers of poly-phenlyenevinylene (PPV) have been examined. An internal space charge field is formed which has been used to quench the luminescence intensity in these materials by separating optically generated excitons and electron-hole pairs. The absorption and emission spectra and the time dependence of the emission of donor and acceptor derivatized block co-polymers was measured and the quenching of the luminescence was observed and quantified. PPV materials with this internal field have potential applications as solar energy converters and photodetectors.