Thermal Effect Of Dual Frequency Laser Based On ANSYS Simulation And Experimental Research

Due to the advantages of high conversion efficiency,compact structure,stable signal output and relatively low cost,the solid-state semiconductor(LD)pumped solid-state microchip laser has become one of the hot topics in the field of solid-state lasers.In the field of optical communication,millimeter-wave technology also has great application prospect and value in the upcoming commercial 5G network.The use of optical methods to generate millimeter-wave signals,heterodyne beat-frequency techniques to obtain good quality RF signals need to provide good coherence dual-band signals.Compared to using two separate single-frequency laser output dual laser signals for heterodyne,the use of dual-wavelength laser is a better choice.Because dual-frequency laser signals come from the same resonator,the phase consistency of the two signals is better than two independently oscillating single-frequency laser sources.However,dual-frequency signal output power ratio will directly affect the heterodyne beat frequency effect.At present,there are few reports about the power balance tuning of the dual-frequency signal output.Therefore,it is very meaningful to study the power tuning and the maximum power product of the dual-frequency output signal in this paper.From this point of view,this paper first studies the theory of the related thermal effect of the crystal when the dual-frequency microchip laser works,and obtains some conclusions through the simulation analysis.The fourth chapter provides a theoretical reference for experimental research.The specific content of this article can be divided into the following aspects:(1)A brief overview of some background of solid-state lasers is given,and the choice of crystal gain materials is introduced in this paper.Then,the research reports of the microchip lasers in recent years are summarized.(2)Described the basic theory of laser generation,and made a detailed introduction to the optical resonator,including the classification,structure and starting conditions of the optical resonator.Then the crystal material used herein belong to four-level structure,a four-level derivation rate equation given longitudinal mode output conditions described expression.(3)The temperature control module in the working process of the microchip laser is modeled,and the theoretical model of the simulation analysis is established.Around the established model,with the help of finite element analysis software,the relationship among the central point temperature and the pumping current and the temperature during the working process is explored.It is found that there is a linear relationship between the pumping current and the temperature.When the pumping current is increased,the temperature control temperature is lowered by the specified value,which can achieve the non-oscillation of the crystal internal temperature.(4)An experimental study on the tunable mechanism of the microchip laser is given,and how to achieve the power balance problem by tuning temperatrue is discussed.According to the conclusion of the third chapter of thermal analysis,when the pumping current of the dual-frequency laser is increased,the power balance of the dual-band signal can be achieved by adjusting the specified temperature,which achieves the tunability of the dual-band power balance signal.