In material systems with several interacting degrees of freedom, the complex interplay between these factors can give rise to exotic phases; now superlattices consisting of alternating layers of PbTiO3 and SrTiO3 are found to exhibit an unusual form of ferroelectric ordering in the PbTiO3 layers, in which the electric dipoles arrange themselves into regular, ordered arrays of vortex–antivortex structures.
- A. K. Yadav
- C. T. Nelson
- R. Ramesh