The impact of flexoelectricity on materials, devices, and physics

In dielectric materials, due to the flexoelectric effect, a large inhomogeneous deformation can break or significantly alter the inversion symmetry of the material and induce net polarization. Such a phenomenon is distinctive comparing to other forms of electromechanical coupling, such as piezoelectricity and electrostriction, in that it is an intrinsic and universal effect whose strength scales up with the decrease in the sample size. Research works in the past decade indicate that the emergence of flexoelectricity not only provides a new way of realizing electromechanical coupling, but also has impact on multiple fields including smart materials, devices, and even physics. Our objective of this perspective is to briefly introduce the field of flexoelectricity and discuss on its future development. Also, current challenges and ambiguities that may impede the further development of the field are pointed out. Furthermore, our opinions on why flexoelectricity matters and how can we use it in novel ways are presented.