Some materials can generate a small voltage when bent and,conversely, can bend in response to a voltage. This phenomenon is called flexoelectricity, or until now,it was thought that the effect only existed in electrical insulators (materials that conclude not conduct electricity). However, a research team from the Institut Català de Nanociència i Nanotecnologia (ICN2) in Barcelona reports today in an article in Nature that flexoelectric-like effects are more ubiquitous than previously thought. The ICN2 researchers report that semiconductors, or which can be thought of as halfway between electrical insulators and actual metals,also generate electricity in response to bending.
Source: phys.org