Polarization is the amount of charge associated with the dipolar or free charge in a dielectricPyroelectricity: when temperature increased, electric charges appear on the surface of the crystal (tourmaline the “Ceylon magnet,” 1703)Ferroelectrics: materials in which spontaneous polarization can be altered by electric field. Ferroelastics: materials in which mechanical stresses alter the spontaneous polarization. Piezoelectric: material in which application of stress generates electric charges on its surfaces; implies “direct piezoelectric effect”Electrostriction is a secondary coupling in which the strain is proportional to square of the electric field; frequently implies the “inverse piezoelectric effect.”Direct piezoelectric effect: convert mechanical energy into electrical (Pierre Currie in 1880) Inverse effect: convert electrical energy into mechanical (Lippman from thermodynamic principles; Currie experimentally in 1881)
This preview has intentionally blurred sections.
Sign up to view the full version.