Direct control of mode-locking states of a fiber laser

Mode locking is a non-equilibrium steady state. Capability to mode-locking states can be used to improve performance as well as shed light on non-equilibrium physics using laser as an experimental platform. We demonstrate direct of the mode-locking state using spectral pulse shaping incorporating a spatial light modulator at a Fourier plane the cavity of an Yb-doped fiber laser. We show that we halt and restart mode locking, suppress instabilities, induce controlled reversible and irreversible transitions between -locking states, and perform advanced pulse shaping using pulses as short as 40 fs.