Polarization Coding in CO2 Lasers: Spatial and Temporal Behavior

We study the polarization dynamics in a CO₂ laser, showing a transition from stable to bistable states and the presence of coherent resonance when noise is added. We discuss the role of optical feedback to achieve polarization stabilization or alternation between first order transverse modes. We discuss the potential applications of this dynamics showing that polarization of a given transverse mode can be controlled by means of a suitable polarized optical feedback. In this way, information can be encoded in the polarization process and it can be safely recovered at an identical laser receiver synchronized with the sender.