Ferroelectrics are a class of materials that exhibit so-called spontaneous electric polarization, which is the separation of electric charges that can be reversed when an external electric field is applied to them. The dipole moments (i.e., pairs of equal and opposite charges) in these materials can sometimes be arranged in complex configurations known as topological textures.

The topological structures of some ferroelectric materials can interact with light in interesting and unexpected ways, which could have interesting implications for the development of optical technologies and communication systems. The size of ferroelectric polar topologies unveiled and studied to date, however, is not aligned with that of laser light modes, which limited their previous use for the development of optical technologies.

Researchers at Nanjing University recently realized a micrometer-scale center-convergent ferroelectric topology using barium titanate (BaTiO₃) membranes that enables the precise spatial control of light fields.