We numerically study the splitting of light beam which carries orbital angular momentum (OAM) through single metal nano-scale hole. A light beam carrying with OAM has a helical phase distribution in the transverse plane, where the electric field has the form: <i>E(r,θ)</i>=<i>E<sub>0</sub>exp(lθ)</i>, and l is the topological charge which denotes the value of OAM. The circular polarization state is corresponding to the spin angular momentum (SAM), where s=+1 represents the left-handed polarization and s=-1 the right-handed polarization. Simulation results show l dependent splitting of beam through nano metal hole. When l is odd, the transmitted far field splits while no splitting happens when l is even. This phenomenon is attributed to the interaction between OAM beam and plasmonic mode of metal nano-hole. It is revealed that different OAM beam can excite different transverse mode in the metal cavity, which means the interaction should obey an OAM section rule. We show that even l can excite transverse mode with zero total AM and odd l can excite transverse mode with non-zero total AM within the hole. Orbital-spin conversion is also revealed in the free wave/plasmon interaction.
Organic solar cells show a commercially viable future duo to their inherent advantages, such as light weight, flexibility,
and so on. Recently, a lot of progress has been made in every domain of organic solar cells. Among these, plasmonic
light trapping is regarded as a promising light management technology for improving the light absorption in organic
active layer. In this work, we numerically investigate the light enhancement in organic solar cell by embedding metal
gratings as electrodes, including the anode and cathode. The absorption enhancement mechanism is analyzed, and the
effects of grating parameters and incident angle are also investigated systematically. The results show the plasmonic
gratings, especially the bottom grating, have an obvious improvement for light harvesting in organic layer, and an optical
enhancement factor about 100% is obtained.
Proc. SPIE. 4924, Holography, Diffractive Optics, and Applications
KEYWORDS: Electronics, High power lasers, Phase shift keying, Laser beam propagation, Adaptive optics, Near field, Optical simulations, Optics manufacturing, National Ignition Facility, Laser systems engineering
Based on the analysis of phase aberrations in high power laser system, the phase corrector plate is presented to correct the static phase aberration. It can greatly improve the performance of the focal spot and is regarded as the suitable supplement of adaptive optics. In this paper, the performance of phase corrector plate, both continuous structure and multi-steps structure, is analyzed and simulated. The effect of misalignment between the phase corrector plate and the laser beam on the focal spot is also presented and simulated.
Diffractive optics is a rapidly developing branch of optics involved computer generated holography, kinoform technology, microelectronics and microfabrication technology. Fabricating some diffractive optics through optical lithography is an effective method. For optimizing lithography process of manufacturing diffractive optics, surface profiles of deep relief gratings are simulated in this paper. Different photoresists are used in the simulations, and simulation results are discussed.