Polarization Properties Of Partially Coherent Vortex Beams In Atmospheric Turbulence Transmission

The propagation and transformation of the partially coherent light is main topic in the modem optics. The partially coherent light plays an important role in the development of modem optics theory and laser technologies. The vortex beam having particular phase and polarization distribution can be widely applied in trapping and guiding small particles and in biomedicine. Moreover, the vortex beams which possess phase or polarization singularity have extensive applications in optical communication and optical information storage.Based on the Huygens-Fresnel principle, the theory formulated in terms of the 2×2 cross-spectral density matrix and the unified theory of coherence and polarization of partially coherent beams, the properties of vortex beams are investigated. Moreover, by the Spiral phase plate the vortex beam is obtained. The main contents of this Dissertation are organized as:(1)The changes of the degree of polarization of partially coherent vortex beams transmitted through a circular ring are investigated. Based on the Huygens-Fresnel principle and the unified theory of coherence and polarization of partially coherent beams, the degree of polarization of partially coherent vortex beams has been investigated. It is shown that the degree of polarization will change after the beam transmitted through the circular ring, and the degree of polarization of the diffractive beam is related with the coherence of source, the topological charges of the source, and the size of the circular ring by theoretical analysis and numerical calculations.(2)The propagation properties of partially coherent vortex beam in free space are investigated. Based on the generalized Huygens-Fresnel principle and the recent theory formulated in terms of the 2×2 cross-spectral density matrix and the propagation laws of cross-spectral density, the propagation properties of partially coherent vortex beam in free space are investigated, including the changes in Stokes parameters and degree of polarization.(3)The propagation properties of partially coherent vortex beam in a turbulent atmosphere are investigated. Based on the Huygens-Fresnel principle and the unified theory of coherence and polarization of partially coherent beams, we investigate the propagation characteristics of partially coherent vortex beam in a turbulent atmosphere. The intensity distribution, Stokes parameters and the degree of polarization of partially coherent vortex beam is dependent on atmosphere turbulent, topological charge and original degree of coherence.