Fiber fuse effect in hollow optical fibers.

We examined nonlinear fiber fuse effect (FFE) in hollow optical fibers (HOFs) that consist of a central air hole surrounded by a high-index ring core and silica cladding. In contrast to conventional solid-core fibers, the HOF with a hole diameter of 4 μm showed high threshold power of 4 W, and resulted in unique tadpole-like voids in periodic arrays after the FFE. As the hole diameter increased to 6 μm, plasma propagation was suppressed within the distance of 1 mm inside of the HOF. Detailed comparisons were made in terms of threshold power, void formation, and penetration length.