[1] [1] Fomin V, Mashkin A, Abramv M, et al. 3 kW Yb fibre lasers with a single-mode output [C]. International Symposium on High-Power Fiber Lasers and Their Applications, 2006.

[2] [2] Evans G A, Hammer J M. Surface Emitting Semiconductor Lasers and Arrays [M]. Boston: Academic Press Inc., 1993.

[3] [3] Siegman A E. How to (maybe) measure laser beam quality [C]. OSA Annual Meeting, 1997.

[4] [4] Mei Z R, Zhao D M, Zheng C W. Analytical expressions of generalized M2 factor of hard-edged diffracted Laguerre-Gaussian beams [J]. Optik, 2005, 116: 337-342.

[5] [5] Li Y Z, Qian L J, et al. Coherent and incoherent combining of fiber array with hexagonal ring distribution [J]. Optics ＆ Laser Technology, 2007, 39: 957-963.