Propagation and focusing characteristics of the Bessel–Gaussian beam with the spiral phase term of new power-exponent-phase

Abstract

A new type of beam called the NPEP-BG (a Bessel–Gaussian (BG) beam with a spiral phase term of a new power-exponent-phase (NPEP)) is theoretically studied in this paper. The results show that the number of singularities of the phase and side lobes of the intensity of this beam were equal to the topological charges (TCs) and the beam has the characteristics of self-healing during propagation. The NPEP-BG beam combined the partial characteristics of the new power-exponent-phase vortex (NPEPV) and the Bessel–Gaussian beam. At the focus of the beam, the characteristic like a perfect vortex beam was present, in which the focal radius is stable and independent of the topological charge. There are multi-focal spots around a ring in the focal plane, meaning that the NPEP-BG beam has a potential for application in multi-particle manipulation.