Papers by Keyword: Nano-Grating

Abstract: Metal nanostructures can be used to control light transmission on the nanometer scale. In this paper, we propose a ladder-type comb-like metal nano-grating structure, based on optical filtering properties of the comb-like nanostructures and surface plasmon resonance effect of the metal nano-structures. The comb part of the structure is the silver nano-grating with the width of 20nm and a depth difference of 5nm between the adjacent gratings. We use the 532nm CW laser as the incident light source to study the reflective properties of the P polarized light and calculate the reflected power spectrum of the structure in three different parameters, which are the silver nano-grating, the silver-air nano-grating (silver grating are separated by air) and silver-SiO2 nano-grating. The experimental results show that the light wave oscillation modes are closely related to the comb-like structure parameters (including the depth and width) on the power spectrum. Meanwhile, we also draw conclusions that different intervention media does not change the position of the light wave oscillation modes, but only a significant effect on the reflection intensity of the different modes. Furthermore, we also noted that the depth of silver nano-gratings can affect the position of the resonance peak. As the waveguide depth of the silver nano-gratings increasing, the spacing of different modes’ oscillation peak is becoming larger. Based on the finding, we can modulate the light wave oscillation modes in a very wide spectral range. The results of this paper will promote the development of the optical filter, light wave mode selection and random laser excitation.

Abstract: This paper presents the simulation results of top nano-grating on solar cell using rigorous coupled wave analysis (RCWA) method. However, compared to other simulation results, we calculated weighted total transmission of solar cell according to Sun spectrum and Silicon photo detector responsivity. Our optimization shows that the top grating with period 200nm, width 40nm, and height 150nm is the optimization structure. This case has 0.45544 total weighted transmission powers and is about 70.9% improvement compared to the non-grating case.

Abstract: The uniform, well designed nano-gratings have been successfully fabricated by using a dual beam focused ion beam (FIB)/scanning electron microscopy (SEM) system on the silicon substrates coated with 15 nm thick Au layer. The nano-gratings were designed with period of 840 nm, groove of 425 nm and beam of 415 nm. By adjusting the FIB parameters of milling like beam current, dwell time and scanning model, the fabricated nano-gratings were uniform in width and the side wall had good verticality. The currently fabricated nano-gratings using focused ion beam can be adjusted to serve as sub-wavelength optical resonant sensor which can be extended to nano-grating accelerometer with resolution of 10^-9g.

Abstract: In this paper, a novel nano-moiré grating fabrication technique was proposed for nanometer deformation measurement. The grating fabrication process was performed with the aid of Atomic Force Microscope (AFM) on the basis of micro-fabrication technique. On the analysis of some correlative factors of influencing grating line quality, some important experimental parameters were optimized. In this study, some parallel and cross nano-gratings with frequencies of from 10000lines/mm to 20000lines/mm were fabricated. The successful experimental results demonstrate that the nano-grating fabrication technique is feasible and also indicated that these nano-gratings with nano-moiré method can be applied to deformation measurement, which offers a nanometer sensitivity and spatial resolution.