  Particle-like topological structures such as skyrmions and vortices have
garnered ever-increasing interests due to the rich physical insights and
potential broad applications. Here we discover the reversible switching between
polar skyrmion bubbles and ordered vortex arrays in ferroelectric superlattices
under an electric field, reminiscent of the Plateau-Raleigh instability in
fluid mechanics. Electric field phase diagram is constructed, showing wide
stability window for the observed polar skyrmions. This study is a
demonstration for the computational design of ferroelectric topological
structures and field-induced topological phase transitions.
