Spiral Propagation of Polymer Optical Fiber Fuse Accompanied by Spontaneous Burst and Its Real-Time Monitoring Using Brillouin Scattering

We study the propagation behavior of the polymer optical fiber (POF) fuse at a power density up to several tens of kW/cm² (corresponding to subwatt power). The propagation velocity is raised in proportion to the power density, reaching 41 mm/s at 67 kW/cm². We also observe spiral oscillation and spontaneous termination of the fuse propagation, with the latter accompanied by a burst. We then develop a new method of detecting the location of the propagating POF fuse remotely and non visually in real time using Brillouin scattering, which can be clearly observed at such a high power density. This method requires neither additional light injection nor signal integration, and it could be used to monitor the propagating fuse in glass fibers.