Single-mode large-mode-area laser fiber with ultralow numerical aperture and high beam quality.

By using the chelate precursor doping technique, we report on an ytterbium-doped aluminophosphosilicate (APS) large-mode-area fiber with ultralow numerical aperture of 0.036 and effective fundamental mode area of ∼550  μm2. With a bend diameter of 600 mm, the bending loss of fundamental mode LP01 was measured to be <10-3  dB/m, in agreement with the corresponding simulation results, while that of higher order mode LP11 is >100  dB/m at 1080 nm. Measured in an all-fiber oscillator laser cavity, 592 W single-mode laser output was obtained at 1079.64 nm with high-beam quality M2 of 1.12. The results indicate that the chelate precursor doping technique is a competitive method for ultralow numerical aperture fiber fabrication, which is very suitable for developing single-mode seed lasers for high power laser systems.

[1]  A. Tünnermann,et al.  Narrow linewidth, single mode 3 kW average power from a directly diode pumped ytterbium-doped low NA fiber amplifier. , 2016, Optics express.

[2]  J. Sahu,et al.  Bending performance of large mode area multi-trench fibers. , 2013, Optics express.

[3]  J. Limpert,et al.  Low-nonlinearity single-transverse-mode ytterbium-doped photonic crystal fiber amplifier. , 2004, Optics express.

[4]  S. Ramachandran,et al.  Resonant bend loss in leakage channel fibers. , 2012, Optics letters.

[5]  David J. Richardson,et al.  High power fiber lasers: current status and future perspectives [Invited] , 2010 .

[6]  Zhiguang Zhou,et al.  Ytterbium-doped large-mode-area silica fiber fabricated by using chelate precursor doping technique. , 2014, Applied optics.

[7]  Yongmin Jung,et al.  Demonstration of ultra-low NA rare-earth doped step index fiber for applications in high power fiber lasers. , 2015, Optics express.

[8]  Fanting Kong,et al.  Impact of fiber outer boundaries on leaky mode losses in leakage channel fibers. , 2013, Optics express.

[9]  M. Pal,et al.  An Optimized Vapor Phase Doping Process to Fabricate Large Core Yb-Doped Fibers , 2015, Journal of Lightwave Technology.

[10]  S. Fevrier,et al.  Solid-Core Photonic Bandgap Fibers for High-Power Fiber Lasers , 2009, IEEE Journal of Selected Topics in Quantum Electronics.

[11]  Mikhail M. Bubnov,et al.  Optical properties of fibres with aluminophosphosilicate glass cores , 2009 .

[12]  Cesar Jauregui,et al.  High-power fibre lasers , 2013 .

[13]  M. Zervas,et al.  High Power Fiber Lasers: A Review , 2014, IEEE Journal of Selected Topics in Quantum Electronics.

[14]  M. E. Fermann,et al.  Fabrication and characterization of low-loss optical fibers containing rare-earth ions , 1986 .

[15]  J. J. Montiel i Ponsoda,et al.  Ytterbium-doped fibers fabricated with atomic layer deposition method. , 2012, Optics express.

[16]  Almantas Galvanauskas,et al.  Single-mode chirally-coupled-core fibers with larger than 50 µm diameter cores. , 2014, Optics express.

[17]  Xiaolong Wang,et al.  Yb-Doped Aluminophosphosilicate Laser Fiber , 2016, Journal of Lightwave Technology.

[18]  Jay R. Simpson,et al.  Raman and NMR spectroscopy of SiO2 glasses CO-doped with Al2O3 and P2O5 , 1988 .

[19]  Aoxiang Lin,et al.  Research progress of chelate precursor doping method to fabricate Yb-doped large-mode-area silica fibers for kW-level laser , 2015 .

[20]  Kunimasa Saitoh,et al.  Ytterbium-doped large-mode-area all-solid photonic bandgap fiber lasers. , 2014, Optics express.