Researches On The Properties And Applications Of Microresonator Based Optical Frequency Comb

Optical frequency comb(OFC)is a series of equidistant frequency lines that enables a variety of new applications in metrology and spectroscopy.Conventional OFCs are generated in mode-locked lasers,which consist of a train of ultra-short pulses in time domain.Recently,microresonator based OFC has been discovered.This approach provides access to high repetition rates in the range of 10 to 1000 GHz,through robust compact,chip-scale integration,permitting an increase number of comb applications,such as spectroscopy,telecommunicaitons,optical waveform synthesis and microwave photonics.However,due to the complexity of the third order nonlinear effects in the cavity,microresonator based OFC has a lot to be studied in theory and experiment.This thesis focuses on the modeling,algorithm design,simulation,experimental platform and application of microresonator based OFC.In this thesis,the theoretical model of silicon nitride based microresonator has been established,and the algorithms are designed and simulated.The effects of pump power,dispersion and Raman effects on the optical frequency comb are analyzed through simulation.Meanwhile,microresonator based soliton has been studied.The principle of stable soliton has been explained from the physical point of view.Through simulation,the uncontrollable factor of the existing soliton formation scheme has been pointed out.The thesis has proposed a new method for controllable frequency line spacing soliton formation in microresonators by pumping the resonator with two continuous wave pumps.Only two steps are needed for soliton formation and only two fixed values of detuning are needed,thus without the tuning speed problem.In addition,the method proposed in the thesis has better control over the amount and location of the solitons traveling in the cavity compared to the tuning pump method.The thesis has also established the theoretical model of silicon based microresonator,and the algorithm is designed and simulated,which can be applied to mid infrared frequency bands.The simulation results show that the most influential factor is the free carrier density,and the solution is pointed out.Compared with the traditional mid-infrared spectral generation device,the silicon resonator based middle-infrared comb has the advantages of ultra-wide spectrum and simple device.Also,the thesis has studied the OFC based millimeter wave signal generation.Verify the feasibility of OFC based millimeter communication through simulation.