A comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier is evaluated. The pump power and thulium-doped fiber (TDF) length for single-pass Thulium-Doped Fiber Amp...A comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier is evaluated. The pump power and thulium-doped fiber (TDF) length for single-pass Thulium-Doped Fiber Amplifiers (TDFA) are theoretically optimized to achieve the optimum Gain and Noise Figure (NF) at the center of S-band region. The 1064 nm pump is used to provide both ground-state and excited state absorptions for amplification in the S-band region. The theoretical result is in agreement with the published experimental result.展开更多
In this paper,we report a coherent beam combining(CBC)system that involves two thulium-doped all-polarization maintaining(PM)fiber chirped pulse amplifiers.Through phase-locking the two channels via a fiber stretcher ...In this paper,we report a coherent beam combining(CBC)system that involves two thulium-doped all-polarization maintaining(PM)fiber chirped pulse amplifiers.Through phase-locking the two channels via a fiber stretcher by using the stochastic parallel gradient descent(SPGD)algorithm,a maximum average power of 265 W is obtained,with a CBC efficiency of 81%and a residual phase error of λ/17.After de-chirping by a pair of diffraction gratings,the duration of the combined laser pulse is compressed to 690 fs.Taking into account the compression efficiency of 90%and the main peak energy proportion of 91%,the corresponding peak power is calculated to be 4 MW.The laser noise characteristics before and after CBC are examined,and the results indicate that the CBC would degrade the low frequency relative intensity noise(RIN),of which the integration is 1.74%in[100 Hz,2 MHz]at the maximum combined output power.In addition,the effects of the nonlinear spectrum broadening during chirped pulse amplification on the CBC efficiency are also investigated,showing that a higher extent of pulse stretching is effective in alleviating the spectrum broadening and realizing a higher output power with decent combining efficiency.展开更多
In this Letter,the optical amplification characteristics of the home-made Bi/P co-doped silica fiber were systematically explored in the range of 1270–1360 nm.The maximum gain of 24.6 dB was obtained in the single-pa...In this Letter,the optical amplification characteristics of the home-made Bi/P co-doped silica fiber were systematically explored in the range of 1270–1360 nm.The maximum gain of 24.6 dB was obtained in the single-pass amplification device,and then improved to 38.3 dB in the double-pass amplification device for-30 dBm signal power.In addition,we simultaneously investigated the laser performance of the fiber with the linear cavity.A slope efficiency of 16.4%at~1313 nm was obtained with a maximum output power of about 133 mW under the input pump power of 869 mW at 1240 nm.As far as we know,it is the first laser reported based on the bismuth-doped fiber in China.展开更多
We report the first demonstration of a unidirectional,isolator-free 2-μm thulium-doped fiber(TDF)laser,relying on the properties of the theta cavity(ring resonator with S-shaped feedback).The core pumped theta cavity...We report the first demonstration of a unidirectional,isolator-free 2-μm thulium-doped fiber(TDF)laser,relying on the properties of the theta cavity(ring resonator with S-shaped feedback).The core pumped theta cavity TDF laser provides sub-Watt output power with a slope efficiency of 25%,a 2 dB flat tuning range of 1900–2050 nm,and a linewidth of 0.2 nm,and achieves the extinction ratio of 18–25 dB(depending on the feedback value)between the favored and suppressed lasing directions.It is shown that these characteristics are competitive with,if not superior to,those of conventional ring cavities.The simulation results of the linear and Kerr-nonlinear theta cavities are also presented,explaining certain unexpected features of the laser behavior and establishing the importance of the doped fiber nonlinearity on the spectral shaping of the emitted signal.展开更多
文摘A comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier is evaluated. The pump power and thulium-doped fiber (TDF) length for single-pass Thulium-Doped Fiber Amplifiers (TDFA) are theoretically optimized to achieve the optimum Gain and Noise Figure (NF) at the center of S-band region. The 1064 nm pump is used to provide both ground-state and excited state absorptions for amplification in the S-band region. The theoretical result is in agreement with the published experimental result.
基金supported in part by the National Key Research and Development Program of China(No.2022YFB3606000)in part by State Key Laboratory of Pulsed Power Laser Technology(No.SKL2020ZR02).
文摘In this paper,we report a coherent beam combining(CBC)system that involves two thulium-doped all-polarization maintaining(PM)fiber chirped pulse amplifiers.Through phase-locking the two channels via a fiber stretcher by using the stochastic parallel gradient descent(SPGD)algorithm,a maximum average power of 265 W is obtained,with a CBC efficiency of 81%and a residual phase error of λ/17.After de-chirping by a pair of diffraction gratings,the duration of the combined laser pulse is compressed to 690 fs.Taking into account the compression efficiency of 90%and the main peak energy proportion of 91%,the corresponding peak power is calculated to be 4 MW.The laser noise characteristics before and after CBC are examined,and the results indicate that the CBC would degrade the low frequency relative intensity noise(RIN),of which the integration is 1.74%in[100 Hz,2 MHz]at the maximum combined output power.In addition,the effects of the nonlinear spectrum broadening during chirped pulse amplification on the CBC efficiency are also investigated,showing that a higher extent of pulse stretching is effective in alleviating the spectrum broadening and realizing a higher output power with decent combining efficiency.
基金supported by the National Key R&D Program of China(No.2020YFB1805902)。
文摘In this Letter,the optical amplification characteristics of the home-made Bi/P co-doped silica fiber were systematically explored in the range of 1270–1360 nm.The maximum gain of 24.6 dB was obtained in the single-pass amplification device,and then improved to 38.3 dB in the double-pass amplification device for-30 dBm signal power.In addition,we simultaneously investigated the laser performance of the fiber with the linear cavity.A slope efficiency of 16.4%at~1313 nm was obtained with a maximum output power of about 133 mW under the input pump power of 869 mW at 1240 nm.As far as we know,it is the first laser reported based on the bismuth-doped fiber in China.
基金This work is supported in part by the SNSF under grant agreement 200021_140816.
文摘We report the first demonstration of a unidirectional,isolator-free 2-μm thulium-doped fiber(TDF)laser,relying on the properties of the theta cavity(ring resonator with S-shaped feedback).The core pumped theta cavity TDF laser provides sub-Watt output power with a slope efficiency of 25%,a 2 dB flat tuning range of 1900–2050 nm,and a linewidth of 0.2 nm,and achieves the extinction ratio of 18–25 dB(depending on the feedback value)between the favored and suppressed lasing directions.It is shown that these characteristics are competitive with,if not superior to,those of conventional ring cavities.The simulation results of the linear and Kerr-nonlinear theta cavities are also presented,explaining certain unexpected features of the laser behavior and establishing the importance of the doped fiber nonlinearity on the spectral shaping of the emitted signal.
