Long-Period Grating Filter Based On Surface Plasmon Metal Waveguide

In recent years, surface plasmon is studied by many researchers, lots of its’ innovative applications and benefits have been widely studied. In sub-wavelength optics, light source, near-field optics, Surface-Enhanced Raman Scattering (SERS), data storage, solar cells, biochemical sensing and other fields all have a good prospect. In particular, surface plasmon waveguide, which is a collection of light, metal, dielectric, electricity etc., due to its advantages in realizing sub-wavelength structures, it is considered the next generation of circuit boards-optoelectronic-integrated circuit board’s core research content. The corresponding optical devices based on surface plasmon waveguide, such as couplers, modulators, light sources, filters, switches and others also need more research.Because all kinds of devices based on surface plasmon waveguide have the necessary of researching, a lot of application scenarios of such devices are combining light and electricity, and in consideration of surface plasmon wave generating mechanism that is the coupling between electromagnetic wave and metal surface electron density waves form surface plasmon polariton, hence current must have some influence on surface plasmon polariton, so it is worthy of reaserching. Then produce a long-period grating on a new type of dielectric loaded surface plasmon polariton waveguide, to verify the possibility of such structure be a filter, and by using long-period grating center wavelength environmentally-sensitive properties attempt to characterize the impact of electric field or current on surface plasmon wave, thus to have a better understanding of the surface plasmon wave under the electric field and current, and in turn guide the designing of surface plasmon waveguide structure comprising electric element in future.The main work:1. Design a dielectric-loaded surface plasmon polariton metal waveguide with a low refractive index layer. The loss of structure designed is close to the typical structure of a metal strip, the mode field restraint ability is similar, but the manufacturing process is relatively simple and easy to add the electrode structure.2. Analysis of the phenomenon that loss of the LRSPP mode supported by above novel structure change with the low refractive index layer gap width.3. The design of the long-period grating located on the surface of the above mentioned new type surface plasmon polariton waveguide, so that the waveguide supports long-range surface plasmon mode and the cladding mode and coupling occurs between these two modes.4. The laboratory completion of the above work of physical analysis, and joined the conducting electrode on the metal film.5. Test and discuss the loss characteristic of the new structure, filtering effects and the temperature drift effect of the grating, and finally by using the electrode structure, observe and analyze the effect of electric fields and currents on surface plasmon wave.