The professional practice is an important scientific research and practice compulsory part for full-time professional master.Sufficient and high-quality professional practice is a significant guarantee of quality of p...The professional practice is an important scientific research and practice compulsory part for full-time professional master.Sufficient and high-quality professional practice is a significant guarantee of quality of professional degree education.The graduate workstation based on enterprises has been explored and the professional and practical ability of postgraduate with major degree has been promoted.展开更多
In this work,a confined-doped fiber with the core/inner-cladding diameter of 40/250μm and a relative doping ratio of 0.75 is fabricated through a modified chemical vapor deposition method combined with the chelate ga...In this work,a confined-doped fiber with the core/inner-cladding diameter of 40/250μm and a relative doping ratio of 0.75 is fabricated through a modified chemical vapor deposition method combined with the chelate gas deposition technique,and subsequently applied in a tandem-pumped fiber amplifier for high-power operation and transverse mode instability(TMI)mitigation.Notably,the impacts of the seed laser power and mode purity are preliminarily investigated through comparative experiments.It is found that the TMI threshold could be significantly affected by the seed laser mode purity.The possible mechanism behind this phenomenon is proposed and revealed through comprehensive comparative experiments and theoretical analysis.Finally,a maximum output power of 7.49 kW is obtained with the beam quality factor of approximately 1.83,which is the highest output power ever reported in a forward tandem-pumped confined-doped fiber amplifier.This work could provide a good reference and practical solution to improve the TMI threshold and realize high-power high-brightness fiber lasers.展开更多
基金funded by the Shandong province postgraduate educational innovation and plan projects.“A Research on the Implementation and Management in Professional Practice of the Full-time Professional Master”(serial number:SDYY16039)。
文摘The professional practice is an important scientific research and practice compulsory part for full-time professional master.Sufficient and high-quality professional practice is a significant guarantee of quality of professional degree education.The graduate workstation based on enterprises has been explored and the professional and practical ability of postgraduate with major degree has been promoted.
基金supported by the National Natural Science Foundation of China(62035015)the Innovative Research Groups of Hunan Province(2019JJ10005)the Hunan Provincial Innovation Construct Project(2019RS3018).
文摘In this work,a confined-doped fiber with the core/inner-cladding diameter of 40/250μm and a relative doping ratio of 0.75 is fabricated through a modified chemical vapor deposition method combined with the chelate gas deposition technique,and subsequently applied in a tandem-pumped fiber amplifier for high-power operation and transverse mode instability(TMI)mitigation.Notably,the impacts of the seed laser power and mode purity are preliminarily investigated through comparative experiments.It is found that the TMI threshold could be significantly affected by the seed laser mode purity.The possible mechanism behind this phenomenon is proposed and revealed through comprehensive comparative experiments and theoretical analysis.Finally,a maximum output power of 7.49 kW is obtained with the beam quality factor of approximately 1.83,which is the highest output power ever reported in a forward tandem-pumped confined-doped fiber amplifier.This work could provide a good reference and practical solution to improve the TMI threshold and realize high-power high-brightness fiber lasers.
