Design,Manufacture And Application Of Periodical Micro-Nano Photonic Nanostructures

In the past ten years,micro-nano optics and photonics are rapidly developed.Periodical micro-nano photonic functional devices such as sub-wavelength gratings,photonic crystals and metamaterials have been widely researched in many fields,for example,optical communication,display illumination,information storage,life sciences,energy technologies,and so on.This paper mainly studied the design,manufacture and application of periodical micro-nano photonic structures in thin film solar cells,biological sensors and quantum dot light emitting devices.The specific research contents and results are summarized as follows:(1)We have designed a variety of light trapping structures in thin film solar cells based on 1-D and 2-D composite gratings,and we used rigorous coupled wave analysis(RCWA)and finite difference time domain(FDTD)method for calculation and simulation.The results show that the nano antireflection structure and surface plasmon polaritons could improve the light absorption efficiency vastly in thin-film solar cells.1-D grating window enhances the TM polarized light absorption effectively,but it is not sensitive to TE light.However,the 2-D symmetrical structure in x-y plane could eliminate the effect of light polarization.On the back reflection electrode,localized surface plasmon resonance effect could be induced by 2-D nano metallic structures.When the period is 220 nm,the diameter of surface dielectric cylinder is 154 nm,the reflector is metal-dielectric-metal structure and the radius of metal cylinder is 16.5nm,the inner and outer radius of the metal ring is 60.5nm and 88nm,the photocurrent reaches up to 39.1mA/cm2,close to the limit value of photocurrent which is 42.2mA/cm2.(2)We studied 2-D annular photonic crystals in the application of biosensors.We systematically calculated the band gap of 2-D annular photonic crystal and its variation characteristics when the annular refractive index changes.The results show that the annular hole unit could effectively depress the working frequency of upper band gap in 2-D photonic crystals,accordingly gaining greater sensitivity than ordinary air holes.The refractive index detection sensitivity of biosensor based on 2-D annular photonic crystal could be as high as 738 nm/RIU,beyond the limit of 2-D air hole photonic crystal biosensor as 500 nm/RIU.Meanwhile,we firstly put forward the cross polarization approach to define the working styles of 2-D photonic crystal biosensor.This method needs the support of TE and TM polarization working mode at the same time,and the sensitivity is the sum of two polarizations,therefore,it is especially suitable for 2-D annular photonic crystals.The simulation results show that the optimal structure increases the refractive index sensitivity to 1190nm/RIU,and it will effectively promote the development and application of 2-D photonic crystal biosensors.(3)We studied 2-D annular photonic crystals in the application of quantum dot light emitting devices.The 2-D annular photonic crystal microcavity is applied in InAs quantum dot light emitting device model,and we achieved a very sharp transmission peak near 1.3?m in the photonic crystal plane both at the TE and TM polarization thanks to the good support of both two polarizations in 2-D annular photonic crystal.The Q value in the plane reached 105?106 orders of magnitude,which can effectively improve the InAs quantum dot light emitting efficiency in this band.At the same time,we adopted FIB for the preparation of 2-D annular photonic crystal microcavity.The results show that FIB could satisfy the requirement of etching precision and high repeatability of the air ring after optimizing etching parameters.In addition,we experimentally verified the performance of 2-D photonic crystal quantum dot light emitting device with the photoluminescence test and the results are in conformity with the simulation.