Tight Focusing of Circular Partially Coherent Radially Polarized Circular Airy Vortex Beam

作者：Zhihao Wan, Haifeng Wang, Cheng Huang, Zhimin He, Jun Zeng, Fu‐Chang Chen, Chaoqun Yu, Yan Li, Huanting Chen, Jixiong Pu, Huichuan Lin · 发表于：Photonics · 年份：2023 · DOI：10.3390/photonics10111279 · 被引用次数：5 · 研究领域：Orbital Angular Momentum in Optics、Sperm and Testicular Function、Microfluidic and Bio-sensing Technologies

The tight focusing properties of circular partially coherent radially polarized circular Airy vortex beams (CPCRPCAVBs) are theoretically studied in this paper. After deriving the cross-spectral density matrix of CPCRPCAVBs in the focal region of a high-NA objective, numerical calculations were performed to indicate the influence of the topological charge of the vortex phase on intensity distribution, degree of coherence and degree of polarization of the tightly focused beam. An intensity profile along the propagation axis shows that a super-length optical needle (~15 λ) can be obtained with a topological charge of 1, and a super-length dark channel (~15 λ) is observed with a topological charge of 2 or 3. In the focal plane, the rise in the number of topological charge does not distort the shapes of the coherence distribution pattern and the polarization distribution pattern, but enlarges their sizes.