Non-Linear Optical Response of Silica Glass Core Fibers Under Intense Pulsed Reactor Irradiation

Importance of non-linear optical responses of optical fibers for diagnostics of fusion plasma is discussed. The light emission and transient optical loss of KU-1 (Russia) and K-3 (Japan) fibers during pulsed reactor irradiation (pulse duration 80 µs, dose rate <7 2 1016 n/cm2s) have been measured in the visible region. The intensity of fast component of light emission obeys sub-linear dose rate dependence. The intensity of radiation-induced light emission and the transient optical loss depend on intensity of probing light.