scholarly journals High power all-fiberized and narrow-bandwidth MOPA system by tandem pumping strategy for thermally induced mode instability suppression

2018 ◽  
Vol 6 ◽  
Author(s):  
Pengfei Ma ◽  
Hu Xiao ◽  
Daren Meng ◽  
Wei Liu ◽  
Rumao Tao ◽  
...  
Keyword(s):  
Output Power ◽  
High Power ◽  
Phase Modulation ◽  
Stimulated Raman Scattering ◽  
Brillouin Scattering ◽  
Beam Quality ◽  
Mode Instability ◽  
Thermally Induced ◽  
Narrow Bandwidth ◽  
Maximal Output Power

An all-fiberized and narrow-bandwidth master oscillator power amplification (MOPA) system with record output power of 4 kW level and slope efficiency of 78% is demonstrated. Tandem pumping strategy is tentatively introduced into the narrow-bandwidth MOPA system for thermally induced mode instability (TMI) suppression. The stimulated Brillouin scattering (SBS) effect is balanced by simply using one-stage phase modulation technique. With different phase modulation signals, SBS limited output powers of 336 W, 1.2 kW and 3.94 kW are respectively achieved with spectral bandwidths accounting for 90% power of ${\sim}$0.025, 0.17 and ${\sim}$0.89 nm. Compared with our previous 976 nm pumping system, TMI threshold is overall boosted to be ${>}$5 times in which tandem pumping increases the TMI threshold of ${>}$3 times. The beam quality ($M^{2}$ factor) of the output laser is well within 1.5 below the TMI threshold while it is ultimately saturated to be 1.86 with the influence of TMI at maximal output power. Except for SBS and TMI, stimulated Raman scattering (SRS) effect will be another challenge for further power scaling. In such a high power MOPA system, multi-detrimental effects (SBS, SRS and TMI) will coexist and may be mutual-coupled, which could provide a well platform for further comprehensively investigating and optimizing the high power, narrow-bandwidth fiber amplifiers.

scholarly journals Novel constant-cladding tapered-core ytterbium-doped fiber for high-power fiber laser oscillator

2021 ◽  
Vol 9 ◽  
Author(s):  
Yun Ye ◽  
Xianfeng Lin ◽  
Xiaoming Xi ◽  
Chen Shi ◽  
Baolai Yang ◽  
...  
Keyword(s):  
Fiber Laser ◽  
Output Power ◽  
High Power ◽  
Stimulated Raman Scattering ◽  
Beam Quality ◽  
Maximum Output Power ◽  
Maximum Output ◽  
Power Scaling ◽  
Laser Oscillator ◽  
Optical Efficiency

Abstract Power scaling based on traditional ytterbium-doped fibers (YDFs) is limited by optical nonlinear effects and transverse mode instability (TMI) in high-power fiber lasers. Here, we propose a novel long tapered fiber with a constant cladding and tapered core (CCTC) along its axis direction. The tapered-core region of the fiber is designed to enhance the stimulated Raman scattering (SRS) threshold and suppress higher-order mode resonance in the laser cavity. The CCTC YDF was fabricated successfully with a modified chemical vapor deposition (MCVD) method combined with solution doping technology, which has a cladding diameter of 400 μm and a varying core with a diameter of ~24 μm at both ends and ~31 μm in the middle. To test the performance of the CCTC fiber during high-power operation, an all-fiber laser oscillator based on a CCTC YDF was investigated experimentally. As a result, a maximum output power of 3.42 kW was achieved with an optical-to-optical efficiency of 55.2%, although the TMI effect was observed at an output power of ~3.12 kW. The measured beam quality (M2 factor) was ~1.7, and no sign of the Raman component was observed in the spectrum. We believe that CCTC YDF has great potential to simultaneously mitigate the SRS and TMI effects, and further power scaling is promising by optimizing the structure of the YDF.

Suppression of Stimulated Brillouin Scattering in High Power Narrow-Linewidth Fiber Amplifier with Phase-Modulation

2011 ◽  
Vol 38 (11) ◽  
pp. 1105009 ◽  
Author(s):  
杜文博 Du Wenbo ◽  
王小林 Wang Xiaolin ◽  
韩凯 Han Kai ◽  
周朴 Zhou Pu ◽  
许晓军 Xu Xiaojun ◽  
...  
Keyword(s):  
High Power ◽  
Phase Modulation ◽  
Brillouin Scattering ◽  
Stimulated Brillouin Scattering ◽  
Fiber Amplifier ◽  
Narrow Linewidth ◽  
Stimulated Brillouin

scholarly journals High-power long-wave infrared laser based on polarization beam coupling technique

2020 ◽  
Vol 8 ◽  
Author(s):  
Yingjie Shen ◽  
Chuanpeng Qian ◽  
Xiaoming Duan ◽  
Ruijun Lan
Keyword(s):  
Output Power ◽  
High Power ◽  
Beam Quality ◽  
Maximum Output Power ◽  
Infrared Laser ◽  
Maximum Output ◽  
Coupling Technique ◽  
Long Wave ◽  
Beam Coupling ◽  
Long Wave Infrared

We demonstrated a high-power long-wave infrared laser based on a polarization beam coupling technique. An average output power at $8.3~\unicode[STIX]{x03BC}\text{m}$ of 7.0 W was achieved at a maximum available pump power of 107.6 W, corresponding to an optical-to-optical conversion of 6.5%. The coupling efficiency of the polarization coupling system was calculated to be approximately 97.2%. With idler single resonance operation, a good beam quality factor of ${\sim}1.8$ combined with an output wavelength of $8.3~\unicode[STIX]{x03BC}\text{m}$ was obtained at the maximum output power.

scholarly journals Study of dopant concentrations on thermally induced mode instability in high-power fiber amplifiers

Laser Physics ◽  
2016 ◽  
Vol 26 (6) ◽  
pp. 065103 ◽  
Author(s):  
Rumao Tao ◽  
Pengfei Ma ◽  
Xiaolin Wang ◽  
Pu Zhou ◽  
Zejin Liu
Keyword(s):  
High Power ◽  
Fiber Amplifiers ◽  
Mode Instability ◽  
Thermally Induced

scholarly journals Monolithic high-average-power linearly polarized nanosecond pulsed fiber laser with near-diffraction-limited beam quality

2018 ◽  
Vol 6 ◽  
Author(s):  
Long Huang ◽  
Pengfei Ma ◽  
Daren Meng ◽  
Lei Li ◽  
Rumao Tao ◽  
...  
Keyword(s):  
Fiber Laser ◽  
Output Power ◽  
Linear Polarization ◽  
Beam Quality ◽  
Average Power ◽  
Narrow Linewidth ◽  
High Average Power ◽  
Maximal Output Power ◽  
Maximal Output ◽  
Pulsed Fiber Laser

An all-fiberized high-average-power narrow linewidth ns pulsed laser with linear polarization is demonstrated. The laser system utilizes a typical master oscillator power amplifier (MOPA) configuration. The stimulated Brillouin scattering (SBS) is effectively suppressed due to the short fiber length and large mode area in the main amplifier, combined with the narrow pulse duration smaller than the phonon lifetime of SBS effect. A maximal output power of 466 W is obtained with a narrow linewidth of ${\sim}$203.6 MHz, and the corresponding slope efficiency is ${\sim}$80.3%. The pulse duration is condensed to be ${\sim}$4 ns after the amplification, corresponding to the peak power of 8.8 kW and the pulse energy of $46.6~\unicode[STIX]{x03BC}\text{J}$. Near-diffraction-limited beam quality with an $M^{2}$ factor of 1.32 is obtained at the output power of 442 W and the mode instability (MI) is observed at the maximal output power. To the best of our knowledge, this is the highest average output power of the all-fiberized narrow linewidth ns pulsed fiber laser with linear polarization and high beam quality, which is a promising source for the nonlinear frequency conversion, laser lidar, and so on.

scholarly journals Análisis de los efectos dispersivos y no lineales de un canal óptico empleando métodos numéricos

Ingenius ◽  
2014 ◽  
pp. 5
Author(s):  
Arturo Peralta Sevilla ◽  
Milton Tipán Simbaña ◽  
Ferney Amaya Fernández
Keyword(s):  
Fourier Transform ◽  
Raman Scattering ◽  
Phase Modulation ◽  
Stimulated Raman Scattering ◽  
Brillouin Scattering ◽  
Single Mode ◽  
Single Mode Fiber ◽  
Cross Phase Modulation ◽  
Self Phase Modulation ◽  
Stimulated Brillouin

En este documento, presentamos el modelado de un canal de fibra óptica mediante la resolución de la Ecuación No Lineal de Schrödinger (NLSE). Se presentan las dos formas de solución para la NLSE: la forma analítica y la forma numérica empleando el método SSF (Split–Step Fourier Transform). En la simulación se consideran efectos lineales como la dispersión cromática y los efectos no lineales. Uno de los efectos no lineal es el efecto Kerr, del que se derivan los efectos de auto modulación fase (Self Phase Modulation, SPM) y modulación de fase cruzada (Cross Phase Modulation, XPM). Los métodos de solución son empleados para simular y visualizar los efectos de propagación a través de la fibra óptica. Se analizan los efectos de propagación para un escenario de red de acceso óptica con fibra mono–modo estándar (Single Mode Fiber, SMF), con longitudes de fibra de 20 y 40 km y tasas de bits entre 1,25 y 100 Gbps. De otro lado, son presentados los fenómenos no lineales como dispersión estimulada de Raman (Stimulated Raman Scattering, SRS) y dispersión estimulada de Brillouin (Stimulated Brillouin Scattering, SBS). Se presentan las ecuaciones para modelar SRS. Se presentan resultados de simulación de la amplificación Raman en un escenario seleccionado.

scholarly journals High-repetition-rate and high-power picosecond regenerative amplifier based on a single bulk Nd:GdVO4 crystal

2019 ◽  
Vol 7 ◽  
Author(s):  
Jie Guo ◽  
Wei Wang ◽  
Hua Lin ◽  
Xiaoyan Liang
Keyword(s):  
Output Power ◽  
High Power ◽  
Repetition Rate ◽  
Beam Quality ◽  
Maximum Output Power ◽  
High Repetition Rate ◽  
Maximum Output ◽  
Bifurcation Instability ◽  
Regenerative Amplifier ◽  
High Repetition

We report on a high-repetition-rate, high-power continuously pumped Nd:GdVO4 regenerative amplifier. Numerical simulations successfully pinpoint the optimum working point free of bifurcation instability with simultaneous efficient energy extraction. At a repetition rate of 100 kHz, a maximum output power of 23 W was obtained with a pulse duration of 27 ps, corresponding to a pulse energy of $230~\unicode[STIX]{x03BC}\text{J}$ . The system displayed an outstanding stability with a root mean square power noise as low as 0.3%. The geometry of the optical resonator and the pumping scheme enhanced output power in the $\text{TEM}_{00}$ mode with a single bulk crystal. Accordingly, nearly diffraction-limited beam quality was produced with $M^{2}\approx 1.2$ at full pump power.

Sign in / Sign up

Export Citation Format

Share Document