Frequency characteristics of a gas coupled-cavity ring laser

Based on a theoretical model describing the lasing dynamics in a gas ring laser (GRL) with coupled cavities, we have investigated the frequency characteristics of radiation. The conditions are found under which an increase in the scale factor is the largest. The regime of frequency locking of counterpropagating waves is studied. It is shown that the lock-in region in a GRL with an antiphase optical coupling of the cavities remains the same as without an additional cavity. The conditions are determined under which multistability of the radiation characteristics arises in a coupled-cavity GRL. In the numerical solution of the equations of the considered theoretical model, three branches of the frequency response are found.