Intensity and polarization dynamics of laser subjected to anisotropic high-order optical feedback

The intensity and polarization dynamics of a laser subjected to anisotropic high-order optical feedback have been investigated. The feedback system is realized by a high-reflectivity feedback mirror and a wave plate in the feedback cavity. The high-resolution optical fringes with nanometer order are obtained owing to the high-reflectivity feedback mirror, and the modulation depth of these optical fringes is relatively uniform, which is different from that of instable fluctuation or intensity noise that has been previously observed. In particular, the polarization flipping is found in each fringe, and the flipping position can be easily changed by rotating the wave plate in the feedback cavity. Furthermore, when the flipping position moves to the edge of each fringe, this optical fringe becomes promising for use in precision measurement. The theoretical analysis based on the compound cavity model and the Floch rotation flipping mechanism is presented, and it agrees well with the experimental results.