Investigation of fiber laser pulses by a fiber-Bragg-grating (FBG) spectrum analyzer

Abstract

We prepared two fiber-Bragg-gratings (FBG)-arrays for the wavelength range 1074 - 1100 nm, both with a spectral width of 0.1 nm and a reflectivity of about 1% of the individual gratings so that pulses are investigated from an Yb fiber laser, Q-switched by an acousto-optical modulator with a repetition rate of 2.6 kHz. Using FBG-array the development of high spikes over some roundtrips in the fiber laser resonator was observed and spectrally analyzed.