Piezoelectricity is created when certain crystals are deformed and can also flex when a current passes through them. It is used in instruments such as tunneling microscopes, sensors, motors, and speakers. Even a tiny piezoelectric crystal can generate thousands of voltages.
Piezoelectricity is a form of electricity created when certain crystals are bent or otherwise deformed. These same crystals can also be made to flex slightly when a small current passes through them, facilitating their use in instruments that require large degrees of mechanical control. This is called reverse piezoelectricity. For example, tunneling microscopes (STM) use piezoelectric crystals to “scan” the surface of a material and create images of great detail. Piezoelectricity is related to pyroelectricity, where a current is created by heating or cooling the crystal.
The property of piezoelectricity is dictated both by the atoms in the crystal and by the particular way that crystal formed. Some of the earliest substances used to demonstrate piezoelectricity are topaz, quartz, tourmaline, and brown sugar. Today we know of many crystals that are piezoelectric, some of which can even be found in human bones. Some ceramics and polymers have also shown the effect.
A piezoelectric crystal consists of multiple interconnected domains that have positive and negative charges. These domains are symmetrical within the crystal, causing the crystal as a whole to be electrically neutral. When the crystal is stressed, the symmetry is slightly broken, generating voltage. Even a tiny piezoelectric crystal can generate thousands of voltages.
Piezoelectricity is used in sensors, actuators, motors, clocks, lighters and transducers. A quartz watch uses piezoelectricity, as does any flintless cigarette lighter. Ultrasound medical devices create high frequency acoustic vibrations using piezoelectric crystals. Piezoelectricity is used in some engines to create the spark that ignites the gas. Speakers use piezoelectricity to convert incoming electricity into sound. Piezoelectric crystals are used in many high-performance devices to apply small mechanical displacements on the nanometer scale.
Although a piezoelectric crystal never deforms more than a few nanometers when a current passes through it, the force behind this deformation is extremely large, on the order of meganewtons. This deformation power is used in mechanical experiments and to align optical elements many times heavier than the piezoelectric crystal itself.
Protect your devices with Threat Protection by NordVPN
