Self-scanned single-frequency operation of a fiber laser driven by a self-induced phase grating

The selector-free single-frequency operation of an Yb-doped fiber laser with scanning in the range of ∼20 nm is demonstrated. The frequency and intensity evolution is shown to be driven by a self-induced phase grating in the active fiber defined by gain saturation in a standing-wave. A theory has been developed that describes well the main features of the experiment and provides possibilities for optimization of laser parameters. Perspectives for utilizing the self-scanned laser in fundamental studies and practical applications are discussed.