Vortex-edge dislocation interaction in the presence of an astigmatic lens

The vortex-edge dislocation interaction in the presence of an astigmatic lens is studied both analytically and numerically, where the effect of astigmatism is stressed. It is shown that for the aberration-free case the edge dislocation bending and break up into a pair of oppositely charged vortices and the shift of the initial vortex appear. The astigmatism leads to some richer vortex evolution behavior. By suitably varying the astigmatic coefficient of the lens, the motion, creation, annihilation and shift to infinity of vortices take place. The off-axis distance additionally affects the vortex evolution behavior for the case of the on-axis vortex and off-axis edge dislocation interaction. In the vortex evolution process the total topological charge is not conserved in general.