Controllable dual auto-focusing electron Pearcey Airyprime beam

Abstract

In this paper, a new type of electron Pearcey Airyprime beam (EPAPB) is proposed and its propagation characteristics in free space and in a constant magnetic field are numerically studied. In free space, the EPAPB achieves, for the first time, clearly separated and tunable dual auto-focusing, giving rise to a controllable electron bottle structure. The number, position, and intensity of the foci, as well as the solid/hollow morphology of the focal spot and the precession direction of the four-lobe pattern, can be flexibly adjusted via several initial parameters, enabling multidimensional wave-packet shaping. In a constant magnetic field, the otherwise single-focus EPAPB in free space displays a tunable dual auto-focusing behavior. The focal positions, intensities, and repetition count are controlled by the field strength, while the induced periodic rotation enables arbitrarily repeatable focusing events.