Study on beam bunching and rotation characteristics of low power laser in permanent magnetic field

In this paper, a test platform based on the Faraday Effect was designed to investigate the beam bunching and rotation characteristics of low power laser in permanent magnetic field. By changing the structural parameters of the permanent magnetic confined cavity, the effects of permanent magnetic field on the rotation characteristics of linearly polarized light and the beam bunching characteristics of low power laser were studied. In the tests of the rotation characteristics of the linearly polarized light, it was found that the rotation angle of linearly polarized light tended to decrease with the increase of the diameter of the magnetic cavity and the decrease of the number of magnets. The maximum rotation angle of linearly polarized light was 142.6°, and the minimum rotation angle was 13.6°. In the tests of beam bunching characteristics of low power laser, it was found that the laser spot area had a slight reduction and the laser power was slightly enhanced when the magnetic flux density increased from 0.4563T to 0.8243T, which proved that the strong magnetic field had a bunching effect on the low power laser.