针对制约单纤系统向更高功率输出面临的泵浦光源亮度受限和有源光纤泵浦注入区域温度控制受限的问题,提出一种新型的端面泵浦耦合器件。通过扩大信号光纤的包层直径,有效提升了可注入光纤系统的泵浦功率,同时有效降低了有源光纤端面泵...针对制约单纤系统向更高功率输出面临的泵浦光源亮度受限和有源光纤泵浦注入区域温度控制受限的问题,提出一种新型的端面泵浦耦合器件。通过扩大信号光纤的包层直径,有效提升了可注入光纤系统的泵浦功率,同时有效降低了有源光纤端面泵浦注入区域的温度。在实验中获得了9.95k W的泵浦激光注入,并在单纤系统中实现了6 k W的输出。该器件具备10 k W以上的泵浦耦合能力,具备应用于万瓦级单纤系统的潜力。展开更多
We demonstrate a compact periodically poled MgO-doped lithium niobate(MgO:PPLN)-based optical parametric oscillator(OPO) quasi-synchronously pumped by a fiber laser system with burst-mode operation.The pump source is ...We demonstrate a compact periodically poled MgO-doped lithium niobate(MgO:PPLN)-based optical parametric oscillator(OPO) quasi-synchronously pumped by a fiber laser system with burst-mode operation.The pump source is a peak-power-selectable pulse-multiplied picosecond Yb fiber laser.The chirped pulses from a figure of eight-cavity modelocked fiber laser seed are narrowed to a duration of less than 50 ps using an FBG reflector and a circulator.The narrowed pulses are directed to pass through a pulse multiplier and to form pulse bunches,each of which is composed of 13 subpulses.The obtained pulse bunches are amplified by two-stage fiber pre-amplifiers:one-stage is core-pumped and the other is cladding-pumped.A fiberized acousto-optic modulator is inserted to control the pulse repetition rate(PRR) of the pulse bunches before they are power-amplified in the final amplifier stage with a large mode area(LMA) PM Yb-doped fiber.The maximum average powers from the final amplifier are 85 W,60 W,and 45 W,respectively,corresponding to the PRR of2.72 MHz,1.36 MHz,and 0.68 MHz.The amplified pulses are directed to pump an MgO:PPLN-based optical parametric oscillator(OPO).A maximum peak power at 3.45 μm is obtained approximately to be 8.4 kW.Detailed performance characteristics are presented.展开更多
A novel evaluation term and a more reasonable criterion,which is described by a new parameter of brightness factor for active large mode area fiber design,are presented.The brightness factor evaluation method is based...A novel evaluation term and a more reasonable criterion,which is described by a new parameter of brightness factor for active large mode area fiber design,are presented.The brightness factor evaluation method is based on the transverse mode competition mechanism in fiber lasers and amplifiers.The brightness factor can be seen as a description of fiber general property since it can represent the output laser brightness of the fiber laser system and because of its ability to resist the nonlinear effect.A core-doped active large pitch fiber with a core diameter of 190 μm and a mode-field diameter of180 μm is designed by this method,and the designed fiber allows effective single-mode operation.展开更多
The steady-state gain distribution in cladding pumped thulium-doped fiber laser(TDFL) is analytically and numerically solved based on the rate equations including loss coefficients and cross relaxation effect. With th...The steady-state gain distribution in cladding pumped thulium-doped fiber laser(TDFL) is analytically and numerically solved based on the rate equations including loss coefficients and cross relaxation effect. With the gain curve, a problem, which is named optical feedback inhibition(OFI) and always occurs in tandem TDFL-Ho:YAG laser system, is analyzed quantitatively. The actual characteristics of output spectra and power basically prove the conclusion of theoretical analysis. Then a simple mirror-deflected L-shaped cavity is employed to restrain the external feedback and simplify the structure of fiber-bulk Ho:YAG laser. Finally, 25 W of 2097-nm laser power and 51.2% of optical-to-optical conversion efficiency are obtained, and the beam quality factor is less than 1.43 obtained by knife-edge method.展开更多
文摘针对制约单纤系统向更高功率输出面临的泵浦光源亮度受限和有源光纤泵浦注入区域温度控制受限的问题,提出一种新型的端面泵浦耦合器件。通过扩大信号光纤的包层直径,有效提升了可注入光纤系统的泵浦功率,同时有效降低了有源光纤端面泵浦注入区域的温度。在实验中获得了9.95k W的泵浦激光注入,并在单纤系统中实现了6 k W的输出。该器件具备10 k W以上的泵浦耦合能力,具备应用于万瓦级单纤系统的潜力。
基金supported by the National Natural Science Foundation of China(Grant No.61078015)the National Basic Research Program of China(Grant No.2011CB311803)
文摘We demonstrate a compact periodically poled MgO-doped lithium niobate(MgO:PPLN)-based optical parametric oscillator(OPO) quasi-synchronously pumped by a fiber laser system with burst-mode operation.The pump source is a peak-power-selectable pulse-multiplied picosecond Yb fiber laser.The chirped pulses from a figure of eight-cavity modelocked fiber laser seed are narrowed to a duration of less than 50 ps using an FBG reflector and a circulator.The narrowed pulses are directed to pass through a pulse multiplier and to form pulse bunches,each of which is composed of 13 subpulses.The obtained pulse bunches are amplified by two-stage fiber pre-amplifiers:one-stage is core-pumped and the other is cladding-pumped.A fiberized acousto-optic modulator is inserted to control the pulse repetition rate(PRR) of the pulse bunches before they are power-amplified in the final amplifier stage with a large mode area(LMA) PM Yb-doped fiber.The maximum average powers from the final amplifier are 85 W,60 W,and 45 W,respectively,corresponding to the PRR of2.72 MHz,1.36 MHz,and 0.68 MHz.The amplified pulses are directed to pump an MgO:PPLN-based optical parametric oscillator(OPO).A maximum peak power at 3.45 μm is obtained approximately to be 8.4 kW.Detailed performance characteristics are presented.
基金supported by the National Natural Science Foundation of China(Grant No.61475081)
文摘A novel evaluation term and a more reasonable criterion,which is described by a new parameter of brightness factor for active large mode area fiber design,are presented.The brightness factor evaluation method is based on the transverse mode competition mechanism in fiber lasers and amplifiers.The brightness factor can be seen as a description of fiber general property since it can represent the output laser brightness of the fiber laser system and because of its ability to resist the nonlinear effect.A core-doped active large pitch fiber with a core diameter of 190 μm and a mode-field diameter of180 μm is designed by this method,and the designed fiber allows effective single-mode operation.
基金Project supported by the National Natural Science Foundation of China(Grant No.61275146)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120002110066)the Special Program of the Co-construction with Beijing Municipal Government of China(Grant No.20121000302)
文摘The steady-state gain distribution in cladding pumped thulium-doped fiber laser(TDFL) is analytically and numerically solved based on the rate equations including loss coefficients and cross relaxation effect. With the gain curve, a problem, which is named optical feedback inhibition(OFI) and always occurs in tandem TDFL-Ho:YAG laser system, is analyzed quantitatively. The actual characteristics of output spectra and power basically prove the conclusion of theoretical analysis. Then a simple mirror-deflected L-shaped cavity is employed to restrain the external feedback and simplify the structure of fiber-bulk Ho:YAG laser. Finally, 25 W of 2097-nm laser power and 51.2% of optical-to-optical conversion efficiency are obtained, and the beam quality factor is less than 1.43 obtained by knife-edge method.
