Interplay of defect dipole and flexoelectricity in linear dielectrics

Flexoelectricity is apparently linearized with the dielectric permittivity and therefore regarded as an inherent dielectric response of solid dielectrics. Herein, we study the role of defect dipole to flexoelectricity by selecting several typical linear dielectrics, wherein the external factors including the surface piezoelectricity, ferroelectricity, and semiconducting interface are strictly eliminated. It is found that the defect dipoles could result in several times enhancement for both the flexoelectric coefficient and the flexocoupling coefficient of the linear dielectrics. The output of this work indicates that introducing defects was a general approach to improve the flexoelectric response. [Display omitted]