Electrical Solid

video of superconducting levitation of ybco

electrical properties include conductivity, resistance, impedance , capacitance. electrical conductors such metals , alloys contrasted electrical insulators such glasses , ceramics. semiconductors behave somewhere in between. whereas conductivity in metals caused electrons, both electrons , holes contribute current in semiconductors. alternatively, ions support electric current in ionic conductors.

many materials exhibit superconductivity @ low temperatures; include metallic elements such tin , aluminium, various metallic alloys, heavily doped semiconductors, , ceramics. electrical resistivity of electrical (metallic) conductors decreases gradually temperature lowered, remains finite. in superconductor however, resistance drops abruptly 0 when material cooled below critical temperature. electric current flowing in loop of superconducting wire can persist indefinitely no power source.

a dielectric, or electrical insulator, substance highly resistant flow of electric current. dielectric, such plastic, tends concentrate applied electric field within property used in capacitors. capacitor electrical device can store energy in electric field between pair of closely spaced conductors (called plates ). when voltage applied capacitor, electric charges of equal magnitude, opposite polarity, build on each plate. capacitors used in electrical circuits energy-storage devices, in electronic filters differentiate between high-frequency , low-frequency signals.

electro-mechanical

piezoelectricity ability of crystals generate voltage in response applied mechanical stress. piezoelectric effect reversible in piezoelectric crystals, when subjected externally applied voltage, can change shape small amount. polymer materials rubber, wool, hair, wood fiber, , silk behave electrets. example, polymer polyvinylidene fluoride (pvdf) exhibits piezoelectric response several times larger traditional piezoelectric material quartz (crystalline sio2). deformation (~0.1%) lends useful technical applications such high-voltage sources, loudspeakers, lasers, chemical, biological, , acousto-optic sensors and/or transducers.