RESUMO
A novel and simple bottom-up fabrication method for the realization of metallic nanovoid and metallic film on nanoparticle (dome) array is presented and their optical performance assessed based on experimental and theoretical investigations. The structures are created by a simple, annealing induced replica formation of a template monolayer, which is composed of submicron particles deposited on top of a thin polymer film. Angle and wavelength dependent reflection measurements indicate the possibility to excite Bragg plasmons at the prepared structures. We found an excellent agreement between the measured and simulated reflection curves, but only when the simulated reflection was averaged over several possible azimuthal lattice orientations of the hexagonal unit cell with respect to the plane of incidence.
RESUMO
We propose a method for performing binary intensity and continuous phase modulation of beams with a spatial light modulator (SLM) and a low-pass spatial filtering 4-f system. With our method it is possible to avoid the use of phase masks in holographic data storage systems or to enhance the phase encoding of the SLM by making it capable of binary amplitude modulation. The data storage capabilities and the limitations of the method are studied.
RESUMO
A new fast-Fourier-transform-based model of a page-oriented holographic data-storage system is presented. The model accounts for essential system and storage material features (e.g. diffraction, noises, and saturation) and provides reliable results in the form of output images, histograms, or bit-error rates. The model is built on a modular basis and provides the possibility of working with different system versions, key components, and storage materials. Applications of the method are presented through examples of optimization of the data density, reference beam size at Gaussian beam illumination, and calculation of the storage medium's positioning tolerances in accordance with the results of test measurements.
