Research On The Generation Of The Structured Light And Its Interactions With Micro-nano Structures

Generation of laser plays an irreplaceable significant role in many scientific areas which has great effects on the improvements of the information technology and human civilization. Structured light generation, phase modulation and optical manipulation have attracted a lot of attentions in last several decades. With the developments of the micro-nano optics, the interactions between light and surface plasmon polaritons and metasurface structure become more and more important. Surface plasmon has a property of condensing wavelength and field enhancement, which provides possibilities to overcome the diffraction limit and modulate light in the micro-nano scale. With the fast development of commercial spatial light modulators, the polarization, phase and amplitude of incident field can be arbitrarily modulated. The incident amplitude and phase have remarkable effects on near-field distributions. So it is possible to provide optimization solutions for many optical problems. Combining the modulations of the incident light and micro-nano structure design, it possesses a great potential in future functional photonics devices and interdiscipline composed of information science, biological and material science. In this dissertation, we realize the generation of the structured light and then theoretically and experimentally study on the interactions between these structured light and SPP structures.This dissertation presents the research works and conclusions, as following:1. Based on the mathematical description of vector beam, we theoretically calculated the focusing properties of the vector beam. The radial polarization has a smaller focus than linear polarization which mainly composed of longitudinal components. We proposed and established a multi-channel structured light generation system based on the Michelson interferometer. With the help of this generation system, we simultaneously realize the modulations of amplitude, phase and polarization in one single setup.2. We investigated the relationship between beam radius and topological charge of vortex phase. And according to this relation curve we show a method for vortex phase detection. We further modulated the vortex phase of the incident light to effectively enhance the excitation of SPP on the silver film. The interference between two optical vortexes has been discussed too. We experimentally realize the generation of Airy beam and Webber beam, which has introduced to excite the SPP on a one-dimensional grating. The SPP distribution in the near-field has been effectively controlled by the incident phase.3. We studied the polarization-dependent optical anisotropic property of the concentric ring plasmonic lens via polarizing microscopy. We proposed a theory model to understand the experimental results and then validated it via numerical simulations. The polarization-dependent optical anisotropy strongly depends on the slit width and separation distance in plasmonic lens. Then we fabricated another L-shape aperture and the experimental results are exactly predicted by the theory model we proposed.4. We have designed and demonstrated a plasmonic Archimedean spiral lens with a central antenna. Unlike a traditional plasmonic lens, which generates a near-field distribution, the central antenna here extracts the bonding SPP field from the surface to produce a vector focal field in far field. By modulating the chirality of the incident circular polarization, the left-handed spiral (one-order chirality) can output micro-radially and circularly polarized focal fields.Highlights in this dissertation are as following:1. We proposed and established a multi-channel structured light generation system based on the Michelson interferometer. The generation system realizes the simultaneous generations of amplitude, phase and polarization in one single setup. The radially and azimuthally polarized light, optical vortex, Airy beam and Webber beam are generated by this system.2. We proposed a theory model to well explain the far-field patterns of the micro-nano structures. Based on this model, the polarization-dependent optical anisotropic has been studied and verified.3. We designed and demonstrated an Archemedean spiral structure combined with a central antenna that can be modulated by the chirality of the incident. By switching the right or left circular polarization, the output polarization can be easily controlled.