High Quality Factor Surface Lattice Resonance Of All-dielectric Metasurfaces And Its Applications

With the development of science and technology,the requirements for miniaturization and integration of optical devices are getting higher and higher.Compared with the traditional optical elements,the two-dimensional metasurfaces have unique electromagnetic response characteristics,and the planar structure means that the manufacturing process is simple.It is also possible to adjust and control the characteristics of light intensity,phase,wavelength and polarization by using structural units of different sizes and shapes and using different arrangement modes.In the field of nano optics,metasurfaces have attracted extensive attention.By arranging nanoparticles into arrays according to a certain period,the local resonance of a single particle and the electromagnetic coupling between surrounding particles will produce a new collective response,which is called surface lattice resonance with higher quality factor.Compared with metal materials,dielectric materials have very low ohmic loss in near infrared or even visible light band,and can be used to design optical metasurfaces with higher quality factor.Based on the finite-difference time-domain method and rigorous coupled wave analysis,the surface lattice resonances in all-dielectric metasurfaces are studied in this thesis,which can be expected to be applied in the fields of laser enhancement and biochemical sensing.This thesis mainly studies the following contents:(1)A silicon-based surface lattice resonance metasurface structure with double resonance peaks is proposed,and a design idea of adjusting two resonance peaks only by changing the period without changing the polarization is given and verified.(2)The finite-difference time-domain method and rigorous coupled wave analysis are used to simulate and design the surface lattice resonance metasurface structure with given wavelengths,and the quality factor in visible light band can be as high as 2600.The influence of structure parameters on its transmission spectrum is analyzed,and the micro-nano machining method of this metasurface is introduced and the metasurface object is prepared.(3)An optical experimental test platform for testing the transflective spectrum of metasurface samples is built,and the metasurface sample is tested experimentally with this test platform.(4)A dielectric metasurface structure of Zn O on a gold mirror is proposed,which has an ultra-high quality factor of 16000 and a FOM of 15930/RIU.The simulation results show that it can be used in refractive index sensing of gas and liquid.