Abstract
Symmetry breaking at surfaces and interfaces and the capability to support large strain
gradients in nanoscale systems enable new forms of electromechanical coupling. Here we
introduce the concept of quantum flexoelectricity, a phenomenon that is manifested when the
mechanical deformation of non-polar quantum systems results in the emergence of net dipole
moments and hence linear electromechanical coupling proportional to local curvature. The
concept is illustrated in carbon systems, including polyacetylene and nano graphitic ribbons.
Using density functional theory calculations for systems made of up to 400 atoms, we
determine the flexoelectric coefficients to be of the order of ~ 0.1 e, in agreement with the
prediction of linear theory. The implications of quantum flexoelectricity on electromechanical
device applications, and physics of carbon based materials are discussed.
