Spectral compression in ring similariton fiber laser

We present a theoretical model of a ring similariton fiber laser employing nonlinear spectrum compression. A pair of tunnel-coupled optical fibers is used for passive mode-locking. The laser characteristics are simulated for a wide range of laser operation regimes and configuration parameters. The optimized laser system design enables generation of pulses with the maximal efficiency and spectral density providing the lowest losses of energy inside the cavity. (letter)