Ferroelectricity is a physical property of a material whereby it exhibits a spontaneous electric polarization, the direction of which can be switched between equivalent states by the application of an external electric field . The term is used in analogy to ferromagnetism, in which a material exhibits a permanent magnetic moment. Ferromagnetism was already known when ferroelectricity was discovered in 1920 in Rochelle Salt by Valasek. Thus, the prefix ferro, meaning iron, was used to describe t… (More on Ferroelectricity)