Generation mechanism on fiber fuse phenomenon in single-mode optical fibers

Unsteady‐state thermal conduction process in the single‐mode (SM) optical fiber was theoretically studied with the explicit finite‐difference method. In the numerical calculation it was assumed that the electrical conductivity of the core layer increased rapidly above 1050 °C. The core‐center temperature changed suddenly and reached over ten thousand Kelvin when the optical power of 1 W was input to the core layer heated above 1000 °C. This rapid heating phenomenon also occurred when the optical power was reflected at the edge wall of the thermally produced cavity in the core layer. The occurrence of this phenomenon was restricted by the decrease in either the input optical power or the normalized frequency of the SM optical fiber. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(11): 11–20, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10150