Steady-state 2π pulses under conditions of passive locking of laser modes

A theoretical study is made of laser mode locking in the regime of self-induced transparency of a passive filter. It is shown that there is a solution in the form of ultrashort steady-state 2π pulses. The range of stability of this regime and its characteristics are determined. By way of example, estimates are obtained of parameters of a steady-state pulse emitted by an alexandrite laser with a potassium absorption cell.