Fiber fuse effect in high-power double-clad fiber laser

In this paper we report the study of fiber fuse effect in large mode area Yb-doped double-clad fiber and Ge-doped double-clad fiber. We can find both periodic and non-periodic void strings in those fibers. This is the first fiber fuse report about the shape of the void in high-power double-clad fiber laser. Furthermore, a heat conduction model is proposed to describe the propagation of the fuse effect in the core of double-clad fiber.