We propose a new class of abruptly autofocusing beams, the chirped annular Bessel Gaussian beams (CABGBs), which are based on the radial Bessel profile. By using the Rayleigh–Sommerfeld diffraction formula, the nonparaxial propagation of the CABGBs is investigated. We find that the initial chirp with negative value tends to intensify the abruptly autofocusing property by shortening the focal length, shrinking the focal spot size, and increasing the peak intensity contrast. The optical trapping effect of the CABGBs acting on a Rayleigh particle is analyzed, and we find that the particle can be stably trapped in three dimensions if the parameters of the CABGBs are appropriate. If the absolute value of the negative chirp increases, the trapping position is shifted toward the input plane, and both the longitudinal and transverse trapping forces rise. A higher magnitude of the radiation forces can be reached if the incident power increases.

我们提出了一种新型的突然自动聚焦光束，即annular形贝塞尔高斯光束（CABGB），它基于径向贝塞尔轮廓。通过使用Rayleigh-Sommerfeld衍射公式，研究了CABGBs的非傍轴传播。我们发现具有负值的初始线性调频趋于通过缩短焦距，缩小焦斑大小并增加峰强度对比度来增强突然的自动聚焦特性。分析了作用于瑞利粒子上的CABGBs的光学俘获效果，我们发现，如果CABGBs的参数合适，则该粒子可以在三个维度上稳定地捕获。如果负线性调频脉冲的绝对值增加，则捕获位置会移向输入平面，并且纵向和横向捕获力都会增加。