Nonlinear theory of multimode action in loss modulated lasers

Abstract

A set of cavity modes which are coupled together by an externally synchronous driven loss modulator is considered. The nonlinear polarization of the material is taken into account, and the mode coupling for the case when many modes are coupled together is treated nearly exactly. The formulas for the pulse shape and pulse width are explicitly derived for the case of a homogeneously broadened line. They show the dependence of these quantities on the system's parameters, such as pump power, modulator driving strength, detuning between modulator frequency, frequency spacing of the cavity modes, etc. Several configurations for the locked modes which have higher pulse widths are possible. This last result in particular seems to be completely new.