Novel Silicon Nanophotonic Waveguides And Microring Resonators

In recent years,silicon photonic integrated circuits have become a popular research topic and the mainstream of next-generation integrated chips due to satisfying the requests for higher signal processing speed,larger bandwidth,smaller device size and better performance.Among various silicon photonic devices,the optical waveguide is the basic component.The microring resonators taking the advantages of simple,compact structure and multifunctions are also exten-sively used in a wide range of applications.This paper is mainly focused on the study of new types of silicon nanophotonic waveguides and microring resonators and their applications.Firstly,the principle of optical waveguides is discussed in detail and a comparative study is given on the sensitivity of SOI(silicon-on-insulator)nanowires and suspended Si nanowires.It is concluded that an optimized suspended Si nanowire for gas sensing possesses ultra high sen-sitivity.Next,a new type hot-wire flowmeter based on silicon ring resonator is proposed,designed and analyzed,having the benefits of being all-optical,namely without any complicated circuits.The size of the flowmeter can be achieved in ultra-small size at micrometer level.The mea-surement is the resonant wavelength drift of the microring,making the sensitivity relatively high.More than this,the use of a SOI chip,compatible with the CMOS process,is good for huge quantity manufacturing with low production costs.Last,the optical force exerts on particles in the evanescent field of a waveguide is demon-strated and calculated.A new type waveguide in silicon,based on the formation of subwave-length gratings(SWG)is presented and analyzed,acquiring that its unique characteristics make particles trapped in both the transverse and longitudinal direction of the waveguide,obviously much better than a common nanowire waveguide.