Photonic Crystal Waveguide And Microcavity Controling Light Properties And Sensing Application Research

Photonic crystals have a wide application prospect in the field of integrated sensing on chip due to its advantages including high sensitivity,ultracompact footprint,small mode volume and more suitable for monolithic integration.As one of the most important structure of photonic crystal,one dimensional photonic crystal waveguide and cavity occupy an important position in the research on sensing application of one-dimensional photonic crystals.This paper does the research on one dimensional photonic crystal sensors based on photonic crystal waveguide and microcavity structure.The fllowing are main research results:(1)it is easy to cause crosstalk for nanobeam icrocavity sensor in multiplexing sensing because of the large resonant peak and small free spectral range.In order to solve the problem,the novel ultra-compact one-dimensional photonic crystal nanobeam integrated sensor is designed based on one-dimensional photonic crystal waveguide and photonic crystal nanobeam cavity.Firstly,one-dimensional photonic crystal nanobeam cavity sensor consists of a one-dimensional photonic crystal nanobeam cavity,with the circle air-hole radius parabolically decreasing.Then,one-dimensional photonic crystal nanobeam bandstop filter is design to matching with cavity sensor according to the photonic bandgap properties of photonic crystal waveguide.By connecting bandstop filter and sensor above,the resonance within the stop band of nanobeam bandstop filter will be filtered out,only the goal resonance used for refractive index sensing is left,The free spectral range is increased from the original 40nm to 275nm,which is nearly 7 times larger.it provides conditions for the reuse of photonic crystal sensor array.A high Q-factor of above 1.43 × 1 03 and a high sensitivity of 127.07nm/RIU can be obtained simultaneously,which agrees well with the 122.07nm/RIU obtained above without filter.Integrated sensor proposed in the paper is promising to be used for sensors array、accurate detection and multiplexed sensing.(2)In order to solve the problem of the low figure of merit(FOM)and sensing performance for the traditional microring sensor,a novel high figure of merit(FOM)slotted one dimensional photonic crystal microring resonator is presented based on a photonic crystal microring resonator with an integrated air-slot waveguide,which provides significant localized field,power density enhancements and overcome the shortcomings of the insufficient overlap between the optical field and the analytes over traditional microring resonator.air-holes radius,the slot width,and gap between microring resonator and bus waveguide is explored to improve Q-factor and he figure of merit.Using finie-difference time-domain(FDTD)simulations,the calculated Q-factor of the optimized slotted-1D-PCMR can exceed 105,sensitivity can reach 97.47nm/RIU.Finally,a high the figure of merit is obtained as 6.63×103 increased a lot compared to the traditional microring resonator.Benefiting from high FOM and simple structure,the demonstrated slotted-1D-PCMR is expected to have potential applications in refractive index sensing and on-chip integrated sensor array.All the above research results based on one-dimensional photonic crystal waveguide and cavity provide valuable experience for the design of high quality factor,the FOM,the ultra compact optical sensors.Besides,It has important reference significance and and application value for the on-chip integrated sensor array in the future...