Multisoliton regime of pulse generation by lasers passively mode locked with a slow saturable absorber

The multiphase regime of a solid-state laser with a slow saturable absorber is studied. Solutions to the propagation equations are derived and their range of existence are analyzed. Single-pulse solutions, called solitons, exist for a certain range parameters. With high enough pump power, two or more pulses may be generated sequentially. In the two-pulse case, the pulses can propagate independently if far apart or form a bound state if close. Two-types of bound states are identified for the same set of parameters: asymmetric with unequal pulse amplitude and symmetric with equal pulse amplitude. The values of the parameters are determined where one-, two- or three-soliton solutions exist.