With linearly coupled nonlinear Schrodinger equations,numerical analysis has been performed on the mode locking forming procedure of a fiber laser in the linear cavity configuration.The fiber is Yb-doped multi-core ph...With linearly coupled nonlinear Schrodinger equations,numerical analysis has been performed on the mode locking forming procedure of a fiber laser in the linear cavity configuration.The fiber is Yb-doped multi-core photonic crystal fiber and semiconductor saturable absorber mirror(SESAM) is adopted as the nonlinear transmission element to start mode locking.Because of the noise randomness,initial pulse would be picked out by SESAM in one or more cores which makes the multi-core mode locking quite different from single-core one.The two situations are compared and fully discussed.Mode locking in multi-core photonic crystal fiber laser can be realized only if the couple coefficient between the cores and the temporal overlap between the pulses in different cores are large enough.展开更多
The modal of 18-core photonic crystal fiber laser is discussed and calculated.And corresponding far-field distribution of the supermodes is given by Fresnel diffraction integral.For improving beam quality,the mode sel...The modal of 18-core photonic crystal fiber laser is discussed and calculated.And corresponding far-field distribution of the supermodes is given by Fresnel diffraction integral.For improving beam quality,the mode selection method based on the Talbot effect is introduced.The reflection coefficients are calculated,and the result shows that an in-phase supermode can be locked better at a large propagation distance.展开更多
The thermal properties of photonic crystal fiber(PCF) laser with 18 circularly distributed cores are investigated by using full-vector finite element method(FEM).The results show that the 18-core PCF has a more effect...The thermal properties of photonic crystal fiber(PCF) laser with 18 circularly distributed cores are investigated by using full-vector finite element method(FEM).The results show that the 18-core PCF has a more effective thermal dispersion construction compared with the single core PCF and 19-core PCF.In addition,the temperature distribution of 18-core PCF laser with different thermal loads is simulated.The results show that the core temperature approaches the fiber drawing value of 1800 K approximately when the thermal load is above 80 W/m which corresponds to the pumping power of 600 W approximately,while the coating temperature approaches the damage value of about 550 K when the thermal load is above 15 W/m which corresponds to the pumping power of 110 W approximately.Therefore the fiber cooling is necessary to achieve power scaling.Compared with other different cooling systems,the copper cooling scheme is found to be an effective method to reduce the thermal effects.展开更多
A model based on propagation rate equations is built up for analyzing the multicore Iransverse mode gain distribution in an 18-core photonic crystal fiber （PCF） laser. The two kinds of feedback cavities are used for...A model based on propagation rate equations is built up for analyzing the multicore Iransverse mode gain distribution in an 18-core photonic crystal fiber （PCF） laser. The two kinds of feedback cavities are used for the fiber laser, which are the buttcontact mirror and the Talbot cavity. According to the model, the transverse mode competitions in different feedback cavities are simulated numerically. The results show that the Talbot cavity can improve in-phase supermode gain, while sunnress other sunerrnodes.展开更多
基金supported by National Basic Research Program of China (2006CB806002 and 2010CB327604)the National Natural Science Foundation of China (60838004 and 60978022)+2 种基金the Key Project of Chi-nese Ministry of Education (108032)the Foundation for the Author of National Excellent Doctoral Dissertation of China (2007B34)the Program for New Century Excellent Talents in University (NCET-07-0597)
文摘With linearly coupled nonlinear Schrodinger equations,numerical analysis has been performed on the mode locking forming procedure of a fiber laser in the linear cavity configuration.The fiber is Yb-doped multi-core photonic crystal fiber and semiconductor saturable absorber mirror(SESAM) is adopted as the nonlinear transmission element to start mode locking.Because of the noise randomness,initial pulse would be picked out by SESAM in one or more cores which makes the multi-core mode locking quite different from single-core one.The two situations are compared and fully discussed.Mode locking in multi-core photonic crystal fiber laser can be realized only if the couple coefficient between the cores and the temporal overlap between the pulses in different cores are large enough.
基金supported by the National Basic Research Program of China(No.2010CB327801)the Key Program of National Natural Science Foundation of China(No.60637010)
文摘The modal of 18-core photonic crystal fiber laser is discussed and calculated.And corresponding far-field distribution of the supermodes is given by Fresnel diffraction integral.For improving beam quality,the mode selection method based on the Talbot effect is introduced.The reflection coefficients are calculated,and the result shows that an in-phase supermode can be locked better at a large propagation distance.
基金supported by the National Basic Research Program of China(No.2010CB327801)the Key Program of National Natural Science Foundation of China(No.60637010)the Natural Science Research Project in University of Hebei Province(No.Z2010163)
文摘The thermal properties of photonic crystal fiber(PCF) laser with 18 circularly distributed cores are investigated by using full-vector finite element method(FEM).The results show that the 18-core PCF has a more effective thermal dispersion construction compared with the single core PCF and 19-core PCF.In addition,the temperature distribution of 18-core PCF laser with different thermal loads is simulated.The results show that the core temperature approaches the fiber drawing value of 1800 K approximately when the thermal load is above 80 W/m which corresponds to the pumping power of 600 W approximately,while the coating temperature approaches the damage value of about 550 K when the thermal load is above 15 W/m which corresponds to the pumping power of 110 W approximately.Therefore the fiber cooling is necessary to achieve power scaling.Compared with other different cooling systems,the copper cooling scheme is found to be an effective method to reduce the thermal effects.
基金supported by the National Basic Research Program of China(No.2010CB327801)the Key Program of National Natural Science Foundation of China(No.60637010)
文摘A model based on propagation rate equations is built up for analyzing the multicore Iransverse mode gain distribution in an 18-core photonic crystal fiber （PCF） laser. The two kinds of feedback cavities are used for the fiber laser, which are the buttcontact mirror and the Talbot cavity. According to the model, the transverse mode competitions in different feedback cavities are simulated numerically. The results show that the Talbot cavity can improve in-phase supermode gain, while sunnress other sunerrnodes.
