Dynamic theory of the spike mode of operation of ruby lasers

An analysis of experimental data has disclosed dynamic mechanisms of the spike mode of operation of a ruby laser. Attention is given to the effect on relaxation oscillations of an additional interaction between laser modes due to the nonlinear susceptibility of the active-medium matrix or due to the nonlaser levels of the active centers. It is shown that this additional interaction, which involves the suppression of the weak mode in the presence of the strong mode during spatial nonhomogeneous removal of inversion, leads to undamped pulsations associated with a succession of different types of oscillations.