Numerical analysis of pulse formation in solid-state lasers mode-locked with a linear external cavity

Abstract

We analyse pulse formation in solid-state lasers mode-locked with a linear external cavity with translating mirror. Based on a numerical simulation the mode-locking mechanism is found to be that of an active mode-locking due to the explicitly time-dependent phase shift by the external cavity involving a slowly moving mirror and a non-zero temporal mismatch to the master cavity. Additional pulse shortening and stabilization is performed by the additive pulse mode-locking mechanism arising from self-phase modulation due to a Kerr-type non-resonant nonlinearity in the host crystal of the laser amplifier.