POLARIZATION CHAOS IN AN OPTICALLY PUMPED LASER

We study the steady-state and dynamic behavior of an optically pumped J = 0 --> J = 1 --> J = 0 laser operating with an isotropic ring cavit y and an axial magnetic field, The gain anisotropy induced by a linear ly polarized pump-laser field leads, in the steady state, to locking o f the two circularly polarized components of the laser field, which ac quires a linear polarization parallel to that of the pump field. In th e presence of laser intensity instabilities, however, locking does not occur, and polarization instabilities appear. For the first time to o ur knowledge, polarization chaos has been found in a laser system.