Tight focusing properties of hybrid-order Poincare sphere beams

OPTICS COMMUNICATIONS

卷:426

Article

Dai, Xuebing¹  Li, Yanqiu¹  Liu, Lihui¹ 

[1] Beijing Inst Technol, Sch Opt & Photon, Minist Educ China, Key Lab Photoelect Imaging Technol & Syst, Beijing 100081, Peoples R China

关键词: Diffraction;    Focusing;    Orbital angular momentum states;    Optical vortices;    Polarisation;   

DOI  :  10.1016/j.optcom.2018.05.017

来源: Elsevier

【 摘 要 】

The hybrid-order Poincare sphere (HPS) was proposed to describe high-order vector vortex beams. In this paper, we theoretically study the intensity and longitudinal component phase distribution of tightly focusing HPS beams within a homogeneous and isotropic medium. We analyse the phase and demonstrate the orbital angular momentum (OAM) state distribution of the longitudinal component. Arbitrary OAM states can be obtained by manipulating the order of HPS beams, which comprise two orthogonally circularly polarised vortex beams with topological charges m and n. Meanwhile, the OAM states of the longitudinal component are destroyed when m = -n; otherwise, they split into two parts with topological charges m + 1 and n - 1. The focus intensity distribution is petal-shaped if the two topological charges have opposite signs, where the number of intensity lobes in the focal plane is vertical bar m - n + 2 vertical bar. Moreover, the ratio of the maximum intensities of the longitudinal and total fields depends on the sign and value of the two topological charges, m and n. Finally, we investigate a generalised case of HPS beams, and demonstrate that the focal intensity and phase distribution are also influenced by the coefficients. The results obtained in this paper may facilitate a new application of HPS beams in various fields.

【 授权许可】

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