Abstract

We investigate the average power scaling of two diode-pumped Yb-doped fiber amplifiers emitting a diffraction-limited beam. The first fiber under investigation with a core diameter of 30 µm was able to amplify a 10 W narrow linewidth seed laser up to 2.8 kW average output power before the onset of transverse mode instabilities (TMI). A further power scaling was achieved using a second fiber with a smaller core size (23µm), which allowed for a narrow linewidth output power of 3.5 kW limited by stimulated Brillouin scattering (SBS). We mitigated SBS using a spectral broadening mechanism, which allowed us to further increase the output power to 4.3 kW only limited by the available pump power. Up to this power level, a high slope efficiency of 90% with diffraction-limited beam quality and without any sign of TMI or stimulated Raman scattering for a spectral dynamic range of higher than −80 dB was obtained.

© 2017 Optical Society of America

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References

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  1. T. Eidam, C. Wirth, C. Jauregui, F. Stutzki, F. Jansen, H.-J. Otto, O. Schmidt, T. Schreiber, J. Limpert, and A. Tünnermann, “Experimental observations of the threshold-like onset of mode instabilities in high power fiber amplifiers,” Opt. Express 19(14), 13218–13224 (2011).
    [Crossref] [PubMed]
  2. C. Jauregui, H.-J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
    [Crossref] [PubMed]
  3. H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
    [Crossref] [PubMed]
  4. C. Jauregui, H. J. Otto, F. Stutzki, F. Jansen, J. Limpert, and A. Tünnermann, “Passive mitigation strategies for mode instabilities in high-power fiber laser systems,” Opt. Express 21(16), 19375–19386 (2013).
    [Crossref] [PubMed]
  5. F. Beier, C. Hupel, J. Nold, S. Kuhn, S. Hein, J. Ihring, B. Sattler, N. Haarlammert, T. Schreiber, R. Eberhardt, and A. Tünnermann, “Narrow linewidth, single mode 3 kW average power from a directly diode pumped ytterbium-doped low NA fiber amplifier,” Opt. Express 24(6), 6011–6020 (2016).
    [Crossref] [PubMed]
  6. C. Jauregui, J. Limpert, and A. Tünnermann, “High-power fibre lasers,” Nat. Photonics 7(11), 861–867 (2013).
    [Crossref]
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    [Crossref] [PubMed]
  8. M. N. Zervas, “Transverse mode instability analysis in fiber amplifiers,” Proc. SPIE 10083, 100830M (2017).
    [Crossref]
  9. C. X. Yu, O. Shatrovoy, T. Y. Fan, and T. F. Taunay, “Diode-pumped narrow linewidth multi-kilowatt metalized Yb fiber amplifier,” Opt. Lett. 41(22), 5202–5205 (2016).
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  12. H. Zhan, Q. Liu, Y. Wang, W. Ke, L. Ni, X. Wang, K. Peng, C. Gao, Y. Li, H. Lin, J. Wang, F. Jing, and A. Lin, “5kW GTWave fiber amplifier directly pumped by commercial 976nm laser diodes,” Opt. Express 24(24), 27087–27095 (2016).
    [Crossref] [PubMed]
  13. M. O’Connor, V. Gapontsev, V. Fomin, M. Abramov, and A. Ferin, “Power scaling of SM fiber lasers toward 10kW,” in Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (CD) (2009), paper CThA3.
    [Crossref]
  14. C. Jauregui, H. J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
    [Crossref] [PubMed]
  15. S. Jetschke, S. Unger, M. Leich, and J. Kirchhof, “Photodarkening kinetics as a function of Yb concentration and the role of Al codoping,” Appl. Opt. 51(32), 7758–7764 (2012).
    [Crossref] [PubMed]
  16. O. Arnould and F. Hild, “EPMA Measurements of Diffusion Proles at the Submicrometre Scale,” Mikrochim. Acta 139(1-4), 3–10 (2002).
    [Crossref]
  17. H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
    [Crossref] [PubMed]
  18. B. Soller, D. Gifford, M. Wolfe, and M. Froggatt, “High resolution optical frequency domain reflectometry for characterization of components and assemblies,” Opt. Express 13(2), 666–674 (2005).
    [Crossref] [PubMed]
  19. N. Haarlammert, O. de Vries, A. Liem, A. Kliner, T. Peschel, T. Schreiber, R. Eberhardt, and A. Tünnermann, “Build up and decay of mode instability in a high power fiber amplifier,” Opt. Express 20(12), 13274–13283 (2012).
    [Crossref] [PubMed]
  20. Y. Jeong, A. Boyland, J. Sahu, S. Chung, J. Nilsson, and D. Payne, “Multi-kilowatt Single-mode Ytterbium-doped Large-core Fiber Laser,” J. Opt. Soc. Korea 13(4), 416–422 (2009).
    [Crossref]
  21. C. Schulze, A. Lorenz, D. Flamm, A. Hartung, S. Schröter, H. Bartelt, and M. Duparré, “Mode resolved bend loss in few-mode optical fibers,” Opt. Express 21(3), 3170–3181 (2013).
    [Crossref] [PubMed]
  22. K. H. Lee, K. Lee, Y. Kim, Y. H. Cha, G. Lim, H. Park, H. Cho, and D. Y. Jeong, “Transverse mode instability induced by stimulated Brillouin scattering in a pulsed single-frequency large-core fiber amplifier,” Appl. Opt. 54(2), 189–194 (2015).
    [Crossref] [PubMed]

2017 (1)

M. N. Zervas, “Transverse mode instability analysis in fiber amplifiers,” Proc. SPIE 10083, 100830M (2017).
[Crossref]

2016 (3)

2015 (5)

2013 (3)

2012 (4)

2011 (1)

2009 (1)

2005 (1)

2002 (1)

O. Arnould and F. Hild, “EPMA Measurements of Diffusion Proles at the Submicrometre Scale,” Mikrochim. Acta 139(1-4), 3–10 (2002).
[Crossref]

Arnould, O.

O. Arnould and F. Hild, “EPMA Measurements of Diffusion Proles at the Submicrometre Scale,” Mikrochim. Acta 139(1-4), 3–10 (2002).
[Crossref]

Bartelt, H.

Beier, F.

Boyland, A.

Cha, Y. H.

Chen, J.

Cho, H.

Chung, S.

de Vries, O.

Duparré, M.

Eberhardt, R.

Eidam, T.

Fan, T. Y.

Flamm, D.

Froggatt, M.

Gao, C.

Gifford, D.

Guo, S.

Haarlammert, N.

Hartung, A.

Hein, S.

Hild, F.

O. Arnould and F. Hild, “EPMA Measurements of Diffusion Proles at the Submicrometre Scale,” Mikrochim. Acta 139(1-4), 3–10 (2002).
[Crossref]

Hupel, C.

Ihring, J.

Jansen, F.

Jauregui, C.

C. Jauregui, H. J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H.-J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, J. Limpert, and A. Tünnermann, “High-power fibre lasers,” Nat. Photonics 7(11), 861–867 (2013).
[Crossref]

C. Jauregui, H. J. Otto, F. Stutzki, F. Jansen, J. Limpert, and A. Tünnermann, “Passive mitigation strategies for mode instabilities in high-power fiber laser systems,” Opt. Express 21(16), 19375–19386 (2013).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

T. Eidam, C. Wirth, C. Jauregui, F. Stutzki, F. Jansen, H.-J. Otto, O. Schmidt, T. Schreiber, J. Limpert, and A. Tünnermann, “Experimental observations of the threshold-like onset of mode instabilities in high power fiber amplifiers,” Opt. Express 19(14), 13218–13224 (2011).
[Crossref] [PubMed]

Jeong, D. Y.

Jeong, Y.

Jetschke, S.

Jing, F.

Jung, M.

Ke, W.

Kim, Y.

Kirchhof, J.

Kliner, A.

Kuhn, S.

Lee, K.

Lee, K. H.

Leich, M.

Leng, J.

Li, Y.

Liem, A.

Lim, G.

Limpert, J.

C. Jauregui, H. J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H.-J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H. J. Otto, F. Stutzki, F. Jansen, J. Limpert, and A. Tünnermann, “Passive mitigation strategies for mode instabilities in high-power fiber laser systems,” Opt. Express 21(16), 19375–19386 (2013).
[Crossref] [PubMed]

C. Jauregui, J. Limpert, and A. Tünnermann, “High-power fibre lasers,” Nat. Photonics 7(11), 861–867 (2013).
[Crossref]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

T. Eidam, C. Wirth, C. Jauregui, F. Stutzki, F. Jansen, H.-J. Otto, O. Schmidt, T. Schreiber, J. Limpert, and A. Tünnermann, “Experimental observations of the threshold-like onset of mode instabilities in high power fiber amplifiers,” Opt. Express 19(14), 13218–13224 (2011).
[Crossref] [PubMed]

Lin, A.

Lin, H.

Liu, Q.

Lorenz, A.

Ludewigt, K.

Lv, H.

Ni, L.

Nilsson, J.

Nold, J.

Otto, H. J.

Otto, H.-J.

Park, H.

Payne, D.

Peng, K.

Peschel, T.

Sahu, J.

Sattler, B.

Schmidt, O.

Schreiber, T.

Schröter, S.

Schulze, C.

Shatrovoy, O.

Soller, B.

Strecker, M.

Stutzki, F.

C. Jauregui, H.-J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H. J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H. J. Otto, F. Stutzki, F. Jansen, J. Limpert, and A. Tünnermann, “Passive mitigation strategies for mode instabilities in high-power fiber laser systems,” Opt. Express 21(16), 19375–19386 (2013).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

T. Eidam, C. Wirth, C. Jauregui, F. Stutzki, F. Jansen, H.-J. Otto, O. Schmidt, T. Schreiber, J. Limpert, and A. Tünnermann, “Experimental observations of the threshold-like onset of mode instabilities in high power fiber amplifiers,” Opt. Express 19(14), 13218–13224 (2011).
[Crossref] [PubMed]

Taunay, T. F.

Tünnermann, A.

F. Beier, C. Hupel, J. Nold, S. Kuhn, S. Hein, J. Ihring, B. Sattler, N. Haarlammert, T. Schreiber, R. Eberhardt, and A. Tünnermann, “Narrow linewidth, single mode 3 kW average power from a directly diode pumped ytterbium-doped low NA fiber amplifier,” Opt. Express 24(6), 6011–6020 (2016).
[Crossref] [PubMed]

C. Jauregui, H. J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H.-J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

N. Haarlammert, B. Sattler, A. Liem, M. Strecker, J. Nold, T. Schreiber, R. Eberhardt, A. Tünnermann, K. Ludewigt, and M. Jung, “Optimizing mode instability in low-NA fibers by passive strategies,” Opt. Lett. 40(10), 2317–2320 (2015).
[Crossref] [PubMed]

C. Jauregui, J. Limpert, and A. Tünnermann, “High-power fibre lasers,” Nat. Photonics 7(11), 861–867 (2013).
[Crossref]

C. Jauregui, H. J. Otto, F. Stutzki, F. Jansen, J. Limpert, and A. Tünnermann, “Passive mitigation strategies for mode instabilities in high-power fiber laser systems,” Opt. Express 21(16), 19375–19386 (2013).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

N. Haarlammert, O. de Vries, A. Liem, A. Kliner, T. Peschel, T. Schreiber, R. Eberhardt, and A. Tünnermann, “Build up and decay of mode instability in a high power fiber amplifier,” Opt. Express 20(12), 13274–13283 (2012).
[Crossref] [PubMed]

T. Eidam, C. Wirth, C. Jauregui, F. Stutzki, F. Jansen, H.-J. Otto, O. Schmidt, T. Schreiber, J. Limpert, and A. Tünnermann, “Experimental observations of the threshold-like onset of mode instabilities in high power fiber amplifiers,” Opt. Express 19(14), 13218–13224 (2011).
[Crossref] [PubMed]

Unger, S.

Wang, J.

Wang, X.

Wang, Y.

Wirth, C.

Wolfe, M.

Xiao, H.

Xu, X.

Yu, C. X.

Yu, H.

Zervas, M. N.

M. N. Zervas, “Transverse mode instability analysis in fiber amplifiers,” Proc. SPIE 10083, 100830M (2017).
[Crossref]

Zhan, H.

Zhang, H.

Zhou, P.

Appl. Opt. (3)

J. Opt. Soc. Korea (1)

Mikrochim. Acta (1)

O. Arnould and F. Hild, “EPMA Measurements of Diffusion Proles at the Submicrometre Scale,” Mikrochim. Acta 139(1-4), 3–10 (2002).
[Crossref]

Nat. Photonics (1)

C. Jauregui, J. Limpert, and A. Tünnermann, “High-power fibre lasers,” Nat. Photonics 7(11), 861–867 (2013).
[Crossref]

Opt. Express (11)

T. Eidam, C. Wirth, C. Jauregui, F. Stutzki, F. Jansen, H.-J. Otto, O. Schmidt, T. Schreiber, J. Limpert, and A. Tünnermann, “Experimental observations of the threshold-like onset of mode instabilities in high power fiber amplifiers,” Opt. Express 19(14), 13218–13224 (2011).
[Crossref] [PubMed]

N. Haarlammert, O. de Vries, A. Liem, A. Kliner, T. Peschel, T. Schreiber, R. Eberhardt, and A. Tünnermann, “Build up and decay of mode instability in a high power fiber amplifier,” Opt. Express 20(12), 13274–13283 (2012).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

H.-J. Otto, F. Stutzki, F. Jansen, T. Eidam, C. Jauregui, J. Limpert, and A. Tünnermann, “Temporal dynamics of mode instabilities in high-power fiber lasers and amplifiers,” Opt. Express 20(14), 15710–15722 (2012).
[Crossref] [PubMed]

B. Soller, D. Gifford, M. Wolfe, and M. Froggatt, “High resolution optical frequency domain reflectometry for characterization of components and assemblies,” Opt. Express 13(2), 666–674 (2005).
[Crossref] [PubMed]

C. Schulze, A. Lorenz, D. Flamm, A. Hartung, S. Schröter, H. Bartelt, and M. Duparré, “Mode resolved bend loss in few-mode optical fibers,” Opt. Express 21(3), 3170–3181 (2013).
[Crossref] [PubMed]

C. Jauregui, H. J. Otto, F. Stutzki, F. Jansen, J. Limpert, and A. Tünnermann, “Passive mitigation strategies for mode instabilities in high-power fiber laser systems,” Opt. Express 21(16), 19375–19386 (2013).
[Crossref] [PubMed]

C. Jauregui, H.-J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

C. Jauregui, H. J. Otto, F. Stutzki, J. Limpert, and A. Tünnermann, “Simplified modelling the mode instability threshold of high power fiber amplifiers in the presence of photodarkening,” Opt. Express 23(16), 20203–20218 (2015).
[Crossref] [PubMed]

F. Beier, C. Hupel, J. Nold, S. Kuhn, S. Hein, J. Ihring, B. Sattler, N. Haarlammert, T. Schreiber, R. Eberhardt, and A. Tünnermann, “Narrow linewidth, single mode 3 kW average power from a directly diode pumped ytterbium-doped low NA fiber amplifier,” Opt. Express 24(6), 6011–6020 (2016).
[Crossref] [PubMed]

H. Zhan, Q. Liu, Y. Wang, W. Ke, L. Ni, X. Wang, K. Peng, C. Gao, Y. Li, H. Lin, J. Wang, F. Jing, and A. Lin, “5kW GTWave fiber amplifier directly pumped by commercial 976nm laser diodes,” Opt. Express 24(24), 27087–27095 (2016).
[Crossref] [PubMed]

Opt. Lett. (2)

Proc. SPIE (1)

M. N. Zervas, “Transverse mode instability analysis in fiber amplifiers,” Proc. SPIE 10083, 100830M (2017).
[Crossref]

Other (2)

G. Overton, “IPG Photonics offers world’s first 10 kW single-mode production laser,” http://www.laserfocusworld.com/articles/2009/06/ipg-photonics-offers-worlds-first-10-kw-single-mode-production-laser.html , Laser Focus World (Published 06/17/2009), 12/09/2015.

M. O’Connor, V. Gapontsev, V. Fomin, M. Abramov, and A. Ferin, “Power scaling of SM fiber lasers toward 10kW,” in Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (CD) (2009), paper CThA3.
[Crossref]

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Figures (6)

Fig. 1
Fig. 1 Refractive index profile relative to the pump cladding index of fused silica for the active core regions of fiber 1 and 2.
Fig. 2
Fig. 2 Loss of the fundamental mode as a function of fiber bend diameter for fiber 1 and fiber 2. The attenuation was determined by OFDR-measurements.
Fig. 3
Fig. 3 Experimental high-power amplifier setup used for the characterization of the fibers. The amplifier was pumped at 976nm in counter-propagation direction. The spectral and temporal behavior of the output beam, as well as its beam quality and output power were analyzed. (PM: Power Meter, DM: Dichroic Mirror)
Fig. 4
Fig. 4 (a) Slope efficiency of the amplifier for fiber 1, (b) Optical spectrum at 3.5kW output power with 75dB level ratio of output signal (with 180pm linewidth) to ASE, (c) Photodiode intensity traces of the output signal at two output powers: below and above the TMI threshold, (d) Evolution of the standard deviation of the normalized PD traces with the output power.
Fig. 5
Fig. 5 (a) Slope efficiency of fiber 2 up to an output power of 4.3kW, (b) Optical spectrum at 3.5kW output power with 75dB ratio of the output signal (180pm linewidth) to ASE and spectrum at 4.3kW output power broadened up to a bandwidth of 7nm, (c): Photodiode intensity trace of the output signal at 4.3kW, (d) Normalized standard deviation of PD traces at various output power.
Fig. 6
Fig. 6 Beam quality measurement (M2x = 1.27, M2y = 1.21) for 4.3 kW peak power at 40% duty cycle.

Tables (1)

Tables Icon

Table 1 Overview of the relevant fiber parameters, maximum output power, and limitations, for the fibers under test.

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