Usually a laser is considered as a system that delivers a particular temporal dynamic generation regime, which can betailored by means of cavity parameters or power. By introducing a concept of PT-symmetry, one can achieve differenttypes of stationary regimes, for example, single-mode operation. In the present work we consider a coupled Raman fiberlasers interconnected by means of Mach-Zender interferometer. We numerically investigate such coupled fiber laserswithin a full dynamical model based on nonlinear Schr?dinger equation. Firstly, we show that nonlinearity induced phasestochasticity does not destroy PT-symmetry, but makes PT-symmetric regimes to exist in narrower region of parameters.We study dynamical properties of the generation regimes and find that depending on parameters (pump power and phaseshift), different dynamical regimes have different parity-time properties. We show that by varying PT-properties one canswitch between different dynamic regimes. We also show that if the pump power is fixed, and phase shift is changedfrom zero (a case of fully uncoupled cavities) to the maximum value, the laser transits from generation in PT-brokenregime to a PT-symmetric generation. At the same time, the laser exhibits a simultaneous reverse transition from aturbulent to a laminar generation.
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