Based on vectorial Debye diffraction theory, the spatial correlation properties in the focal region of a J0 -correlated azimuthally polarized vortex beam through a high numerical aperture (NA) are analyzed. The expres...Based on vectorial Debye diffraction theory, the spatial correlation properties in the focal region of a J0 -correlated azimuthally polarized vortex beam through a high numerical aperture (NA) are analyzed. The expressions for a pair of points on the axis of symmetry and for a pair of points in the focal plane are derived. It is found that the longitudinal and transverse coherence lengths in the focal region change with the variation in the topological charge and coherence parameter of the vortex field, together with the NA values. In addition, the degree of coherence is shown to possess phase singularities.展开更多
基金the Natural Science and Technology Project of the Education Bureau of Fujian Province under Grant No JK2011054the Key Engineering Project of the Education Bureau of Fujian Province under Grant No HX200804。
文摘Based on vectorial Debye diffraction theory, the spatial correlation properties in the focal region of a J0 -correlated azimuthally polarized vortex beam through a high numerical aperture (NA) are analyzed. The expressions for a pair of points on the axis of symmetry and for a pair of points in the focal plane are derived. It is found that the longitudinal and transverse coherence lengths in the focal region change with the variation in the topological charge and coherence parameter of the vortex field, together with the NA values. In addition, the degree of coherence is shown to possess phase singularities.
