We demonstrated a 2-μm passively mode-locked nanosecond fiber laser based on a MoS2 saturable absorber（SA）.Owing to the effect of nonlinear absorption in the MoS2 SA, the pulse width decreased from 64.7 to 13.8 ns ...We demonstrated a 2-μm passively mode-locked nanosecond fiber laser based on a MoS2 saturable absorber（SA）.Owing to the effect of nonlinear absorption in the MoS2 SA, the pulse width decreased from 64.7 to 13.8 ns with increasing pump power from 1.10 to 1.45 W. The use of a narrow-bandwidth fiber Bragg grating resulted in a central wavelength and 3-dB spectral bandwidth of 2010.16 and 0.15 nm, respectively. Experimental results show that MoS2 is a promising material for a 2-μm mode-locked fiber laser.展开更多
High-peak-power transform-limited narrow-linewidth nanosecond all-fiber lasers are desired in a range of applications.However,their linewidths will be broadened by self-phase modulation(SPM).We propose a novel concept...High-peak-power transform-limited narrow-linewidth nanosecond all-fiber lasers are desired in a range of applications.However,their linewidths will be broadened by self-phase modulation(SPM).We propose a novel concept that generates transform-limited laser pulses by temporally shaping the pulse seed.The impact of the pulse shape on SPM-induced spectral broadening was studied numerically and experimentally.It was found theoretically that the square-shape pulsed laser is immune to SPM-induced spectral broadening.Based on this principle,we built a high-peak-power,linearly polarized,square-shape nanosecond all-fiber laser in a master oscillator power amplifier(MOPA)configuration.Stimulated Brillouin scattering(SBS)limited peak powers of 4.02 kW,5.06 kW,6.52 kW and 9.30 kW were obtained at pulse widths of 8 ns,7 ns,6 ns and 5 ns.Thanks to the square-shape pulsed seed,the linewidths at maximum peak power remained at 129.5 MHz,137.6 MHz,156.2 MHz and 200.1 MHz,respectively,close to the transform-limited values of110.8 MHz,126.6 MHz,147.7 MHz and 177.3 MHz.展开更多
In this work,we experimentally investigate the dependence of the stimulated Raman scattering(SRS)effect on the seed linewidth of a high-power nanosecond superfluorescent fiber source(ns-SFS).The results reveal that th...In this work,we experimentally investigate the dependence of the stimulated Raman scattering(SRS)effect on the seed linewidth of a high-power nanosecond superfluorescent fiber source(ns-SFS).The results reveal that the SRS in the ns-SFS amplifier is significantly influenced by the full width at half maximum(FWHM)of the ns-SFS seed,and there is an optimal FWHM linewidth of 2 nm to achieve the lowest SRS in our case.The first-order SRS power ratio increases rapidly when the seed’s linewidth deviates from the optimal FWHM linewidth.By power scaling the ns-SFS seed with the optimal FWHM linewidth,a narrowband all-fiberized ns-SFS amplifier is achieved with a maximum average power of 602 W,pulse energy of 24.1 mJ and corresponding peak power of 422.5 kW.This is the highest average power and pulse energy achieved for all-fiberized ns-SFS amplifiers to the best of our knowledge.展开更多
系统研究了窄线宽低噪声单频连续光纤激光器、高能量纳秒长脉冲单频光纤激光器以及高峰值功率纳秒短脉冲光纤激光器三类高性能光纤激光器:实现了工作于1、1.5及2μm波段的单频连续光纤激光器,典型光谱线宽小于3 k Hz,强度噪声接近于散...系统研究了窄线宽低噪声单频连续光纤激光器、高能量纳秒长脉冲单频光纤激光器以及高峰值功率纳秒短脉冲光纤激光器三类高性能光纤激光器:实现了工作于1、1.5及2μm波段的单频连续光纤激光器,典型光谱线宽小于3 k Hz,强度噪声接近于散粒噪声极限;实现了高能量单频光纤激光器,脉冲能量超过200μJ,重复频率20 k Hz,脉冲宽度100~500 ns,激光波长位于1.5μm波段;实现了高峰值功率纳秒短脉冲光纤激光器,峰值功率超过700 k W,重复频率10 k Hz,脉冲宽度3 ns;同时还实现了高重频高峰值功率纳秒短脉冲光纤激光器,峰值功率超过200 W,重复频率3 MHz,脉冲宽度1~5 ns。文中阐述了以上几类高性能光纤激光器在激光雷达探测系统中的应用前景。展开更多
基于线型腔结构实现中心波长约1 945 nm、功率150 m W的连续激光输出,采用3级主振荡功率放大(master oscillator power amplifier,MOPA)结构,实现123 W的掺铥激光输出,斜率效率为59.1%.搭建基于调制半导体激光器,输出波长为1 550 nm的...基于线型腔结构实现中心波长约1 945 nm、功率150 m W的连续激光输出,采用3级主振荡功率放大(master oscillator power amplifier,MOPA)结构,实现123 W的掺铥激光输出,斜率效率为59.1%.搭建基于调制半导体激光器,输出波长为1 550 nm的铒镱共掺光纤放大器,实现平均功率1.2 W、脉宽50 ns、重复频率200 k Hz的脉冲激光输出.将该铒镱共掺光纤放大器作为泵浦源,采用线型腔结构抽运掺铥光纤,实现中心波长约为1 945 nm的增益调制脉冲激光输出,重复频率为100 k Hz,脉宽约为800ns.采用3级MOPA结构对此增益调制掺铥脉冲光纤激光器进行功率放大,实现平均功率115 W、单脉冲能量1.15 m J的激光输出,且放大过程中无非线性效应产生.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11304409)the Natural Science Foundation of Chongqing City,China(Grant No.CSTC2013jcyj A4004)+1 种基金the Scientific and Technological Research Program of Chongqing Municipal Education Commission,China(Grant No.KJ1500422)the Special Theme Projects on LCD Industrial Generic Technology Innovation of Chongqing City,China(Grant No.CSTC2015zdcyztzx40003)
文摘We demonstrated a 2-μm passively mode-locked nanosecond fiber laser based on a MoS2 saturable absorber（SA）.Owing to the effect of nonlinear absorption in the MoS2 SA, the pulse width decreased from 64.7 to 13.8 ns with increasing pump power from 1.10 to 1.45 W. The use of a narrow-bandwidth fiber Bragg grating resulted in a central wavelength and 3-dB spectral bandwidth of 2010.16 and 0.15 nm, respectively. Experimental results show that MoS2 is a promising material for a 2-μm mode-locked fiber laser.
基金supported by the National Natural Science Foundation of China(Nos.61705265 and 61705264)the National Key R&D Programme of China(No.2017YFF0104603)the China Postdoctoral Science Foundation(No.2017M620070)
文摘High-peak-power transform-limited narrow-linewidth nanosecond all-fiber lasers are desired in a range of applications.However,their linewidths will be broadened by self-phase modulation(SPM).We propose a novel concept that generates transform-limited laser pulses by temporally shaping the pulse seed.The impact of the pulse shape on SPM-induced spectral broadening was studied numerically and experimentally.It was found theoretically that the square-shape pulsed laser is immune to SPM-induced spectral broadening.Based on this principle,we built a high-peak-power,linearly polarized,square-shape nanosecond all-fiber laser in a master oscillator power amplifier(MOPA)configuration.Stimulated Brillouin scattering(SBS)limited peak powers of 4.02 kW,5.06 kW,6.52 kW and 9.30 kW were obtained at pulse widths of 8 ns,7 ns,6 ns and 5 ns.Thanks to the square-shape pulsed seed,the linewidths at maximum peak power remained at 129.5 MHz,137.6 MHz,156.2 MHz and 200.1 MHz,respectively,close to the transform-limited values of110.8 MHz,126.6 MHz,147.7 MHz and 177.3 MHz.
基金financially supported by the CAS Project for Young Scientists in Basic Research(No.YSBR-065)the National Natural Science Foundation of China(Nos.62225507,62175230,and U2033211)+1 种基金the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.YJKYYQ20200001)the National Key R&D Program of China(No.2022YFB3607800).
文摘In this work,we experimentally investigate the dependence of the stimulated Raman scattering(SRS)effect on the seed linewidth of a high-power nanosecond superfluorescent fiber source(ns-SFS).The results reveal that the SRS in the ns-SFS amplifier is significantly influenced by the full width at half maximum(FWHM)of the ns-SFS seed,and there is an optimal FWHM linewidth of 2 nm to achieve the lowest SRS in our case.The first-order SRS power ratio increases rapidly when the seed’s linewidth deviates from the optimal FWHM linewidth.By power scaling the ns-SFS seed with the optimal FWHM linewidth,a narrowband all-fiberized ns-SFS amplifier is achieved with a maximum average power of 602 W,pulse energy of 24.1 mJ and corresponding peak power of 422.5 kW.This is the highest average power and pulse energy achieved for all-fiberized ns-SFS amplifiers to the best of our knowledge.
文摘系统研究了窄线宽低噪声单频连续光纤激光器、高能量纳秒长脉冲单频光纤激光器以及高峰值功率纳秒短脉冲光纤激光器三类高性能光纤激光器:实现了工作于1、1.5及2μm波段的单频连续光纤激光器,典型光谱线宽小于3 k Hz,强度噪声接近于散粒噪声极限;实现了高能量单频光纤激光器,脉冲能量超过200μJ,重复频率20 k Hz,脉冲宽度100~500 ns,激光波长位于1.5μm波段;实现了高峰值功率纳秒短脉冲光纤激光器,峰值功率超过700 k W,重复频率10 k Hz,脉冲宽度3 ns;同时还实现了高重频高峰值功率纳秒短脉冲光纤激光器,峰值功率超过200 W,重复频率3 MHz,脉冲宽度1~5 ns。文中阐述了以上几类高性能光纤激光器在激光雷达探测系统中的应用前景。
文摘基于线型腔结构实现中心波长约1 945 nm、功率150 m W的连续激光输出,采用3级主振荡功率放大(master oscillator power amplifier,MOPA)结构,实现123 W的掺铥激光输出,斜率效率为59.1%.搭建基于调制半导体激光器,输出波长为1 550 nm的铒镱共掺光纤放大器,实现平均功率1.2 W、脉宽50 ns、重复频率200 k Hz的脉冲激光输出.将该铒镱共掺光纤放大器作为泵浦源,采用线型腔结构抽运掺铥光纤,实现中心波长约为1 945 nm的增益调制脉冲激光输出,重复频率为100 k Hz,脉宽约为800ns.采用3级MOPA结构对此增益调制掺铥脉冲光纤激光器进行功率放大,实现平均功率115 W、单脉冲能量1.15 m J的激光输出,且放大过程中无非线性效应产生.
