A sensitive method to determine the optic axis azimuth of the birefringence element is presented, which is based on laser feedback. The phase difference between the two intensities in birefringence feedback changes wi...A sensitive method to determine the optic axis azimuth of the birefringence element is presented, which is based on laser feedback. The phase difference between the two intensities in birefringence feedback changes with the angle between the optic axis of the birefringence element and laser original polarization. The phase difference is highly sensitive to the relative position of the optic axis and the laser original polarization. This method is used to highly precisely determine the optic axis azimuth, and is able to distinguish between the fast axis and the slow axis of the birefringence element. Theoretical analysis and experimental results are both demonstrated.展开更多
Through employing permutation entropy and the self-correlation function, the time-delay signature (TDS) of a vertical-cavity surface-emitting laser (VCSEL) with variable-polarization filtered optical feedback (VP...Through employing permutation entropy and the self-correlation function, the time-delay signature (TDS) of a vertical-cavity surface-emitting laser (VCSEL) with variable-polarization filtered optical feedback (VPFOF) is evaluated theoretically. The work shows that the feedback rate η, polarizer angle Op, and filter bandwidth A have an obvious influence on the TDS. The evolution maps of the TDS in parameter space (η, A) and (ηθp) are simulated for searching the chaos with weak TDS. Furthermore, compared with a VCSEL with polarization-preserved filtered optical feedback and a VCSEL with variable-polarization mirror optical feedback, this VPFOF-VCSEL shows superiority in TDS suppression.展开更多
基金Project supported by the Natural Science Foundation of Beijing,China(Grant No.3091002)
文摘A sensitive method to determine the optic axis azimuth of the birefringence element is presented, which is based on laser feedback. The phase difference between the two intensities in birefringence feedback changes with the angle between the optic axis of the birefringence element and laser original polarization. The phase difference is highly sensitive to the relative position of the optic axis and the laser original polarization. This method is used to highly precisely determine the optic axis azimuth, and is able to distinguish between the fast axis and the slow axis of the birefringence element. Theoretical analysis and experimental results are both demonstrated.
基金supported by the National Natural Science Foundation of China(Grant Nos.61178011,61275116,and 61475127)the Graduate Research and Innovation Project of Chongqing Municipality(Grant No.CYB14054)
文摘Through employing permutation entropy and the self-correlation function, the time-delay signature (TDS) of a vertical-cavity surface-emitting laser (VCSEL) with variable-polarization filtered optical feedback (VPFOF) is evaluated theoretically. The work shows that the feedback rate η, polarizer angle Op, and filter bandwidth A have an obvious influence on the TDS. The evolution maps of the TDS in parameter space (η, A) and (ηθp) are simulated for searching the chaos with weak TDS. Furthermore, compared with a VCSEL with polarization-preserved filtered optical feedback and a VCSEL with variable-polarization mirror optical feedback, this VPFOF-VCSEL shows superiority in TDS suppression.