| During the last two decades, plasmonics has been thriving due to its unique property of extreme confinement of electromagnetic (EM) field on metal surface. It provides us the fantastic setting for manipulating light in the regions well below the diffraction limit. SPPs is a promising candidate of future integration photonics since it could work at the scale of electronic devices and the speed of photonic devices, bridging the world of nanoscale electronics and microscale photonics. This thesis mainly concerned the basic principle and probable functions for SPP chips. We proposed some new schemes and methods for SPP manipulation and realized several novel, useful manipulations. The main results of the dissertation are as follows:1. We extended the traditional diffraction principle of optics to 2 dimensional (2D) SPPs and studied the diffraction process of SPPs by nanoarray. The diffraction principle of SPPs under non-perfectly-matched Bragg condition was discovered and experimentally proved. We extended this principle to nonpe the optical field of SPPs in 2D system.2. With this scheme, we demonstrated a realization of plasmonic Airy beam on silver surface totally by in-plane diffraction processes. The revealed SPP Airy beam exhibits the unique features, such as nondiffraction, self-bending and self-healing. The beam can make some compensates to the propagation loss of SPPs as well.3. We worked out a new group of collimated plasmon beams by the means of in-plane diffraction with symmetric phase modulation. Upon this, an intuitive diagram was proposed to elucidate the beam nature and base on this diagram, we further achieved a highly designable scheme to modulate the beam intensity (e.g., "lossless" plasmon). Furthermore, we extended this diagram to realize arbitrary nonmonotonical beams. These revealed beams can be taken as nonconfined waveguides, without suffering the loss from confining structures. This study gives a unique insight into the SPP beam formation and is expected to inspire more intriguing phenomena and potential applications in beam engineering and nanophotonic manipulations.4. The broad band focusing of SPPs was realized by the phase modulation scheme as well and the bandwidth is about 100nm in visible region. The design can be used as a SPP demultiplexer and the resolution is about 12nm. We extended this phase tuning scheme to SPPs from point source and realized several kinds of beams as well, indicating the wide application of the scheme.5. We extended the phase modulation scheme to 3D free space and generate far field optical orbital angular momentum beam (OAM) with SPPs modulated by structures on metal surface. The radical phase modulation process can be integrated together with the generation and we got nondiffration, focusing or off-axis injecting OAM beams. The beam splitting process can be integrated with the generation as well and the according split beams can carry different OAM numbers, which may inspire further research and application of OAM beam in information process.6. We introduce a scheme to reconfiguration of polarization states base on two orthogonal propagating SPPs. The light with the different polarization states will be scattered out of the metal surface by nanostructures and can be analyzed or manipulated by polarization systems. We experimentally verified this scheme and realized polarization controlled beams (such as directional beaming, airy beam, focusing, etc.) based on this scheme. Furthermore, based on the multiplexing of the scatters, multiple desired polarization states in required beam-forms can be realized simultaneously. More importantly, the scheme provides a new dimension of polarization control, which can co-work with other polarization controlled systems (such as the coupling system, metasurface etc.). We did have realized a 2x2 controlled beams, indicating its exciting ability to improve the information capacity. |
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