We have demonstrated that by adding the solution of aggregated silver nanoparticles to the solution of rhodamine 6G dye, one can enhance the efficiency of spontaneous and stimulated emission. We attribute an increase of the spontaneous emission intensity of dye to the increase of the absorption efficiency caused by the field enhancements in metallic nanostructures associated with surface plasmo...

It is demonstrated that recovery of the electromagnetic energy of the fundamental mode at the output of an acceleration structure leads to a significant efficiency enhancement. When using a single bunch, the number of electrons accelerated is rather small. In fact, this number is virtually identical to the case when no feedback loop is employed. To increase this number, in parallel with the eff...

We investigate transmission efficiency and finite size effects for the subwavelength hole arrays. Experiments and simulations show how the finite size effects depend strongly on the hole diameter. The transmission efficiency reaches an asymptotic upper value when the array is larger than the surface plasmon propagation length on the corrugated surface. By comparing the transmission of arrays wi...

We present a theory of the magnetic field enhancement of terahertz (THz) emission from photogenerated carriers in the surface depletion region of a semiconductor. A combination of the Drude-Lorentz model for the carrier dynamics with an appropriate solution of the radiation problem is sufficient to explain the strong B -field enhancement in THz radiation that has been observed experimentally. T...

We present a study of the efficiency and optimization of cw second harmonic generation by elliptical Gaussian laser beams. Elliptical focusing slightly improves conversion efficiency and reduces crystal damage risk when heavy walk-off is present. Single-pass measurements of the efficiency for doubling 5 15-nm radiation in beta-barium borate (BBO) agree with theory. Thermal effects, caused by ra...

Efficient light manipulation at subwavelength scale is of great interest for solar energy conversion, optical sensing, and nanophotonic devices. Recently, plasmonic nanopatch antennas (PNAs), which consist of plasmonic nanoparticles and metal films with thin layers of dielectric spacers sandwiched between them, have shown promise for directing and enhancing radiation from the dipole emitters at...

We experimentally demonstrate cascaded field enhancement by means of gold nanoparticle dimer and trimer antennas. The local field enhancement is probed by single-molecule fluorescence using fluorophores with high intrinsic quantum efficiency (Q(0)>80%). Using a self-similar trimer antenna consisting of 80, 40, and 20 nm gold nanoparticles, we demonstrate a fluorescence enhancement of 40 and a s...

The efficiency of chemical energy production of a photosynthetic system can be strongly enhanced in the presence of metal nanoparticles. Two competing effects contribute to the photosystem efficiency: plasmon enhancement of photon fields inside the light-absorbing chlorophyll molecules and energy transfer from chlorophylls to metal nanoparticles. The first effect can lead to strong enhancement ...

In this paper, we present a novel prism with the ability to enhance the contrast ratio and maintain the optical efficiency in a digital light processing projection system. The working theorem for the novel prism is derived as well. In this novel prism design, the ghost ray is directed away from the projection lens by a total internal reflection surface. Since the ghost ray does not even enter t...

conclusions due to the significant reduction in the mean inactivation dose of colon cancer cells in the presence of gold nanoparticles, it seems that gnps are suitable options to achieve a new approach in order to improve radiotherapy efficiency without increasing the prescribed radiation dose. results cell survival in the presence of gnps was more than 90% and the maximum uptake of gnps was ob...