Polarization selection by optical feedback

Polarized optical feedback and noise effects on CO2laser polarization dynamics: spatial and temporal behavior

“…In previous experiments [9,11], we have reported this bistable condition of the CO 2 laser polarization for different conditions, while here we present evidence that this phenomenon is related also to the laser pump condition which depends on the discharge current. The discharge current is slowly changed between an initial value (6 mA) where the laser is above threshold and no switches between polarization states are observed, to a high value (9 mA) where fast switching occurs.…”

“…In such a case the dynamics is more complicated due to the interplay between laser multimode operation and polarization instabilities. Here we show the effect of a weak optical feedback when a mirror is inserted in the reflection arm (on the TEM 00 mode operation, a weak optical feedback leads to a polarization stabilization) [11].…”

“…Then, in our model the linear anisotropy parameter is included as a noise. Finally, the model reads as [1,9,11] …”

“…The polarization dynamics during the switch-on transient of a quasi-isotropic CO 2 laser emitting on the fundamental mode and TEM Ã 01 mode are reported [9,10]. Recently, using a quasi-isotropic CO 2 laser, it has been shown that it is possible to stabilize the emission of one of the two polarization modes by using an optical feedback and commute the polarization by a fast switch in the feedback arm [11]. In [12] experimental evidence of the in-phase and out-of-phase synchronization of the polarization in two coupled quasi-isotropic CO 2 lasers is reported.…”

Polarization Coding in CO2 Lasers: Spatial and Temporal Behavior

“…Dynamical models have been developed to explore the role of the anisotropy due to the laser medium [1][2][3][4][5][6][7][8]. Recently, using quasi-isotropic class B lasers, it has been shown that it is possible to stabilize the emission on one of the two polarization modes by using an optical feedback and commute the polarization by a fast switch in the feedback arm [9][10][11].…”