Self-sweeping regimes control in a bi-directional Yb-doped ring fiber laser

We report three self-sweeping regimes in a single-mode bi-directional Yb-doped ring fiber laser with increasing pump power: normal self-sweeping operation, wavelength stationary state, and reverse self-sweeping operation. The intensity dynamics of both normal and reverse self-sweeping are a dual-longitudinal-mode quasi-continuous wave formed by alternating the flat and burst regions. In addition, the wavelength stationary state can be achieved at an arbitrary value between 1067.5 nm and 1072.3 nm, depending on the historical process of wavelength self-sweeping, whose intensity dynamics consist of chaotic pulses and periodic bursts. In short, switching wavelength self-sweeping regimes can be achieved simply by changing the pump power. These research results are potentially valuable for developing and applying self-sweeping fiber lasers.