Study On Optical Radiation Characteristics Of Active Microcavity

With the development of electronic devices became the limit,people's demand for information capacity of communication devices is increasing,so that the development of photonic devices came into being.Optical active microcavity lasers,as a kind of stable signal source for integrated optical path,have attracted much attention and research.Microcavity lasers are composed of gain materials and optical resonators,which are defined by the physical size on the order of micrometers or sub-micrometers.The core of the microcavity lasers is the microcavity on the order of micrometers.In this paper,we focus on the optical radiation characteristics of two kinds of active microcavities,and contribute to a more cost-effective and simpler light source for the development of integrated optical path.Details of the optical radiation characteristics of the two types of active microcavities are as follows:1.TiO₂ and SiO₂ films were prepared by sol-gel method and TiO₂ and SiO₂multilayers were prepared by impregnation and pulling method.Finally,two active microcavities,distributed feedback?DFB?and distributed Bragg reflector?DBR?,were designed on the basis of the structure of TiO₂ and SiO₂ multilayers.And the reflectivity of Bragg multilayer was simulated by the transfer matrix method.Next,under the condition of laser-pumped,the optical radiation characteristics of two kinds of active microcavities were studied.The following experimental results were obtained.When the pump light was 532 nm nanosecond pulsed laser,the threshold value of the output light of the DFB active microcavity was 0.2 mJ/pulse,and the full width at half maximum?FWHM?was 7.5 nm.The slope efficiency of amplified spontaneous emission was 3%.The DBR-type active microcavity as a further validation of the sol-gel impregnation and pulling method confirmed good reliability of this method,and the multi-longitudinal mode of the laser was observed.2.The effects of metal nanoparticles on the random laser emission properties of polymer dispersed liquid crystals were investigated by a novel capillary structure.The capillary structure can be used as a pioneer in the study of fiber random lasers.The same is to limit the light in a one-dimensional dimension within the research work.Moreover,we also explored the optimal doping concentration of metal nanoparticles.Finally,the experimental results show that the effects were mainly reflected in the reduction of random laser threshold and the shortening of peak linewidth.And the random laser emission was not only originated from the multiple scattering mechanism,but also originated from the surface plasmon oscillation effect.At the same time,there is a compromise between fluorescence enhancement and fluorescence quenching due to the presence of Pt nanoparticles.The best doping concentration of metal nanoparticles was 1 wt%.The threshold was only 8.7?J/pulse,and the FWHM of the peak was 0.1 nm.Through the above two parts of experiments,we investigate the optical radiation characteristics of three kinds of active microcavities,and provide a stable and low cost light source for the integrated optical path.