Localized surface plasmon excitations in metallic nanoparticles with either absorbing or amplifying media are analyzed. In the case of absorption, we present the first direct measurements of enhanced absorption in two dimensional films of dyes and isolated metallic nanoparticles. These results are of particular importance for enhancing the performance of low cost solar cells by allowing for a reduction in the thickness of amorphous layers that have poor conduction properties. Materials specific to the application of plasmon enhancement of TiO2 dye sensitized solar cells are also described. The situation where the surrounding medium is capable of amplification is studied and the required gains for real metals are determined. In addition, the enhancement of local fields in such systems is estimated and discussed in terms of further enhancing Surface Enhanced Raman Spectroscopy processes for molecular detection.
A high efficiency, narrow spectral linewidth lasing pixel device that implements a low-voltage spatially patterned variable loss element placed inside an optically pumped high-gain laser cavity is experimentally studied. The output properties of this system make it potentially useful for digital projection displays. Coupling and grey-scale control of an intracavity pixelated laser projected system is studied experimentally and by numerical simulation. Results indicate that pixel independence can be maintained in high Fresnel number resonators.
The behavior of second-harmonic generation (SHG) is germanosilicate fibers in compared to recent results on similar effects in semiconductor microcrystallite glasses. The latter offer a much more readily characterizable system where many of the bulk semiconductor properties can be invoked to explain the results. The comparison suggests that extended state enhancement of nonlinear response and electric field dependent trapping in the germanosilicate glass system would unify the encoding process in both materials.