A Self-Excitation Double Pathway Relaxation Oscillational Model of Rare-Earth-Doped Laser

A self-excitation double pathway relaxation oscillation mechanism to deal with the self-pulsing output of upconversion laser with rare-earth ions as the active material is raised. The reabsorption of the laser signal, which causes self-excitation of system and two-pathway transition of system, plays a role of adjusting Q, and causes the oscillation output of laser. A qualitative analysis to the appearance of self-pulsing output of rare-earth-doped laser is given.