Performance of an LD-end-pumped passively Q-switched Nd： YA G/Cr4＋ ： YA G microchip laser operating at 1123 nm is studied. A maximum average output power of 517row with an optical-to-optical conversion efficiency o...Performance of an LD-end-pumped passively Q-switched Nd： YA G/Cr4＋ ： YA G microchip laser operating at 1123 nm is studied. A maximum average output power of 517row with an optical-to-optical conversion efficiency of 12.6% and a slope efficiency of 25.8% is obtained under a pump power of 4.1 W. A minimum pulse width of 1.1 ns with a pulse repetition rate of 20.2kHz is obtained, and the corresponding pulse energy and peak power are 25.6μJ and 23.3kW, respectively. To our knowledge, the 23.3kW peak power is the highest among 1123nm lasers. Additionally, based on the 1123 nm laser, with LBO as the frequency doubler, a 288-mW green-yellow laser at 561 nm is successfully achieved.展开更多
A passive Q-switched large-mode-area Yb-doped fibre laser is demonstrated using a GaAs wafer as the saturable absorber. A high Yb doping concentration double-clad fibre with a core diameter of 30#m and a numerical ape...A passive Q-switched large-mode-area Yb-doped fibre laser is demonstrated using a GaAs wafer as the saturable absorber. A high Yb doping concentration double-clad fibre with a core diameter of 30#m and a numerical aperture of 0.07 is used to increase the laser gain volume, permitting greater energy storage and higher output power than conventional fibres. The maximum average output power is 7.2 W at 1080nm wavelength, with the shortest pulse duration of 580ns and the highest peak power of 161 W when the laser is pumped with a 25 W diode laser operating at 976nm. The repetition rate increases with the pump power linearly and the highest repetition rate of 77kHz is obtained in the experiment.展开更多
An intracavity coherent coupling Michelson erbium-doped fibre （EDF） laser （MCEDFL） is proposed and demonstrated. By using this laser system, we find a means to obtain a maximum power output at the same pumping pow...An intracavity coherent coupling Michelson erbium-doped fibre （EDF） laser （MCEDFL） is proposed and demonstrated. By using this laser system, we find a means to obtain a maximum power output at the same pumping power level. From the experiment based on fibre Bragg gratings （FBGs） with different refiectivities from 6% to 100%, we find that the reflectivity of the FBG plays a vital role in improving the performance of the MCEDFL. At the same time, the MCEDFL with a polarizer can be coherently combined effectively. This type of system, in principle, is compatible with other more powerful pumping methods, such as cladding pumping, and brings some novel perspectives to the realization of high power lasers.展开更多
An intra-cavity coherent coupling Michelson Er-doped fibre （EDF） laser （MCEDFL） is proposed and demonstrated. Characteristics of the MCEDFL are investigated. It is found that the MCEDFL with a polarizer can be coh...An intra-cavity coherent coupling Michelson Er-doped fibre （EDF） laser （MCEDFL） is proposed and demonstrated. Characteristics of the MCEDFL are investigated. It is found that the MCEDFL with a polarizer can be coherent combined effectively. By the experiment based on fibre Bragg gratings （FBGs） with different reflectivity, we find that the reflectivity of the FBG play a vital role in improving the performance of the MCEDFL. This outcome adequately shows many favourable features, such as high efficiency, easy operation, and simple all-fibre configuration.展开更多
In the present study,high-quality apatite-type La9.33Ge6O26 powders are successfully synthesized by a facile moltensalt synthesis method（MSSM） at low temperatures,using Li Cl,Li Cl/Na Cl mixture（mass ratio 1：1） a...In the present study,high-quality apatite-type La9.33Ge6O26 powders are successfully synthesized by a facile moltensalt synthesis method（MSSM） at low temperatures,using Li Cl,Li Cl/Na Cl mixture（mass ratio 1：1） as molten salt,respectively.Experimental results indicate that the optimal mass ratio between reactant and molten salt is 1：2,and Li Cl/Na Cl mixed molten-salt is more beneficial for forming high-quality La9.33Ge6O26 powders than Li Cl individual molten-salt.Comparing with the conventional solid-state reaction method（SSRM）,the synthesis temperature of apatitetype La9.33Ge6O26 powders using the MSSM decreases more than 350℃,which can effectively avoid Ge loss in the preparation process of precursor powders.Furthermore,the powders obtained by the MSSM are homogeneous,nonagglomerated and well crystallized,which are very favorable for gaining dense pellets in the premise of avoiding Ge loss.On the basis of high-quality precursor powders,the dense and pure ceramic pellets of La（9.33）Ge6O（26） are gained at a low temperature of 1100℃ for 2 h,which exhibit higher conductivities（σ850℃（Li Cl）= 2.3 × 10^-2 S·cm^-1,σ850 ℃（Li Cl/Na Cl） = 4.9 × 10^-2 S·cm^-1） and lower activation energies（Ea（Li Cl）= 1.02 e V,Ea（Li Cl/Na Cl）= 0.99 e V） than that synthesized by the SSRM.展开更多
基金Supported by the Foundation of Shandong Province under Grant No J13LN28the National Natural Science Foundation of China under Grant No 11304184
文摘Performance of an LD-end-pumped passively Q-switched Nd： YA G/Cr4＋ ： YA G microchip laser operating at 1123 nm is studied. A maximum average output power of 517row with an optical-to-optical conversion efficiency of 12.6% and a slope efficiency of 25.8% is obtained under a pump power of 4.1 W. A minimum pulse width of 1.1 ns with a pulse repetition rate of 20.2kHz is obtained, and the corresponding pulse energy and peak power are 25.6μJ and 23.3kW, respectively. To our knowledge, the 23.3kW peak power is the highest among 1123nm lasers. Additionally, based on the 1123 nm laser, with LBO as the frequency doubler, a 288-mW green-yellow laser at 561 nm is successfully achieved.
基金Supported by the National High-Technology and Development Programme of China under Grant No 2003CB314906, the Tianjin Natural Science Foundation Projects under Grant No 06YFJZJC00300, and the China Postdoctoral Science Foundation under Grant No 20060390666.
文摘A passive Q-switched large-mode-area Yb-doped fibre laser is demonstrated using a GaAs wafer as the saturable absorber. A high Yb doping concentration double-clad fibre with a core diameter of 30#m and a numerical aperture of 0.07 is used to increase the laser gain volume, permitting greater energy storage and higher output power than conventional fibres. The maximum average output power is 7.2 W at 1080nm wavelength, with the shortest pulse duration of 580ns and the highest peak power of 161 W when the laser is pumped with a 25 W diode laser operating at 976nm. The repetition rate increases with the pump power linearly and the highest repetition rate of 77kHz is obtained in the experiment.
基金Project supported by the Tianjin Natural Science Foundation （Grant No 06YFJZJC00300）, and the National Science Foundation for Postdoctoral Scientists of China （Grant No 20060390666）.Acknowledgement We thank Dr Jin Long and Associate Professor Liu Bo for fruitful discussion.
文摘An intracavity coherent coupling Michelson erbium-doped fibre （EDF） laser （MCEDFL） is proposed and demonstrated. By using this laser system, we find a means to obtain a maximum power output at the same pumping power level. From the experiment based on fibre Bragg gratings （FBGs） with different refiectivities from 6% to 100%, we find that the reflectivity of the FBG plays a vital role in improving the performance of the MCEDFL. At the same time, the MCEDFL with a polarizer can be coherently combined effectively. This type of system, in principle, is compatible with other more powerful pumping methods, such as cladding pumping, and brings some novel perspectives to the realization of high power lasers.
基金Supported by the Tianjin Natural Science Foundation under Grant No 06YFJZJC00300.
文摘An intra-cavity coherent coupling Michelson Er-doped fibre （EDF） laser （MCEDFL） is proposed and demonstrated. Characteristics of the MCEDFL are investigated. It is found that the MCEDFL with a polarizer can be coherent combined effectively. By the experiment based on fibre Bragg gratings （FBGs） with different reflectivity, we find that the reflectivity of the FBG play a vital role in improving the performance of the MCEDFL. This outcome adequately shows many favourable features, such as high efficiency, easy operation, and simple all-fibre configuration.
基金Project supported by the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2016FB16,ZR2015AQ010,and ZR2016AQ08)the Shandong University of Technology at Zibo and Zibo City Integration Development Project,China(Grant No.2016ZBXC205)
文摘In the present study,high-quality apatite-type La9.33Ge6O26 powders are successfully synthesized by a facile moltensalt synthesis method（MSSM） at low temperatures,using Li Cl,Li Cl/Na Cl mixture（mass ratio 1：1） as molten salt,respectively.Experimental results indicate that the optimal mass ratio between reactant and molten salt is 1：2,and Li Cl/Na Cl mixed molten-salt is more beneficial for forming high-quality La9.33Ge6O26 powders than Li Cl individual molten-salt.Comparing with the conventional solid-state reaction method（SSRM）,the synthesis temperature of apatitetype La9.33Ge6O26 powders using the MSSM decreases more than 350℃,which can effectively avoid Ge loss in the preparation process of precursor powders.Furthermore,the powders obtained by the MSSM are homogeneous,nonagglomerated and well crystallized,which are very favorable for gaining dense pellets in the premise of avoiding Ge loss.On the basis of high-quality precursor powders,the dense and pure ceramic pellets of La（9.33）Ge6O（26） are gained at a low temperature of 1100℃ for 2 h,which exhibit higher conductivities（σ850℃（Li Cl）= 2.3 × 10^-2 S·cm^-1,σ850 ℃（Li Cl/Na Cl） = 4.9 × 10^-2 S·cm^-1） and lower activation energies（Ea（Li Cl）= 1.02 e V,Ea（Li Cl/Na Cl）= 0.99 e V） than that synthesized by the SSRM.
