Designing Dielectric Properties by Local Structure Engineering

Here we demonstrate antiferroelectricity and antiferroelectric domain engineering to enhance permittivity in titanite-type oxides. Despite the conventional understanding that antiferroelectric domains, unlike ferroelectric ones, do not provide an additional polarization response due to their non-polar nature, it has been discovered that condensed domain walls（anti-phase boundaries）in titanite-type CaTi（Si1–xGex）O5 cooperatively form polar clusters, markedly enhancing the dielectric permittivity of the system. This finding introduces a new concept of domain engineering in dielectric materials to boost permittivity.