Theoretical calculation of beam quality factor of large-mode-area fiber amplifiers
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In order to evaluate a fiber amplifier’s output beam quality, we have explored the beam quality factor calculation. A theoretical beam quality factor calculation method is presented in this paper. The method bases on modal power decomposition, laser rate equations and Fourier diffraction theory. Through the rate equations, each modal power weight factor at the fiber output facet is obtained. By the modal power decomposition, the optical field at the fiber output facet is established. Finally, running Fourier transformation, the beam diverging state in free space and corresponding M 2 parameter are obtained. The calculation process is verified with applying it to working out the beam M 2 parameters of large-mode-area (LMA) fiber amplifier system under different conditions. The numerical results help us well know and predict the out beam property. Some obtained results are also accord with other reporting outcomes.
PACS numbers42.25.Bs 42.55.Wd 42.60.Jf 42.60.Pk
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- 7.W. Stephan, Opt. Express 15, 15492 (2007).Google Scholar
- 14.A. E. Siegman, http://www.stanford.edu/:_siegman/beam_quality_tutorial_osa.pdf. (1998).
- 17.J. R. Marciante, in Proc. of the Photonic Applications Systems Technologies Conference, PhAST, May 8, Baltimore, Maryland, 2007, Poster Session I, JTuA86.Google Scholar
- 18.J. R. Marciante, in Proc. of the Advanced Solid-State Photonics (ASSP), Vancouver, Canada, Jan. 28, 2007, Poster Session III: WB14.Google Scholar
- 19.M. Hotoleanu, M. São derlund, D. Kliner, J. Koplow, and S. Tammela, in Proc. of SPIE of Fiber Lasers III: Technology, Systems, and Applications, San Jose, CA, USA, 23 Jan. 2006, Vol. 6102, 61021T1.Google Scholar