Controlling Skyrmions' Density (IMAGE) Institute for Basic Science Caption This study measured skyrmions in an ultra-thin material made of a ferromagnetic layer of strontium ruthenate (SrRuO3), overlaid with a ferroelectric layer of barium titanate (BaTiO3) and grown on a strontium titanate (SrTiO3) substrate. BaTiO3 is ferroelectric, meaning that it has a switchable and permanent electric polarization (), while SrRuO3 is ferromagnetic below 160 Kelvin (-113 Celsius). At the BaTiO3/SrRuO3 interface, the BaTiO3 ferroelectric polarization swirls the spins in SrRuO3, generating skyrmions. If the researchers flip the direction of polarization in BaTiO3, the density of the skyrmions changes. Credit IBS Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.