The diversity of operational regimes in an ytterbium-doped fiber laser with a low-Q-factor cavity

Here, we report the unusual behavior of an ytterbium-doped fiber laser with a low-Q-factor cavity characterized by a variety of qualitatively different regimes arising as a result of increasing pump power: from amplified spontaneous emission via self-induced laser line sweeping and self-Q-switching, to narrow-band 'thermal-light' emission. Special attention is paid to a discussion of the statistical and coherent properties of light released by the laser system in the considered operational regimes.