Fig. 7. Q-Switched laser characterization of the AZO-based fiber laser. (a) Typical output pulse spectrum, centered at 1558.2 nm. The inset shows long-term operation. (b) The typical RF spectrum at fundamental frequency and the wideband RF spectrum (inset). (c) The pulse duration and repetition rate as a function of pump power. (d) Output power and pulse energy as a function of pump power.