Piezoelectric effect refers to the ability of certain materials to produce electric polarization under applied mechanical stress. This electric  polarization manifests as a measurable potential difference across the material. One of the unique characteristics of the piezoelectric effect is the reversibility: electric polarization under applied stress, and the generation of stress under an electric field. Therefore, piezoelectric discs work as actuators or sensors by generating vibrational shift when a periodic potential is applied.

Key Features

Piezoelectric materials are widely used in compact actuators such as linear motors, rotary motors, pumps in inkjet printers, and sensors such as pressure sensors and load cells. In microfluidic devices or lab-on-a-chip systems, the direct piezoelectric effect is used in micro-scale chemical and biological sensors.  For example, high-precision mass measurement devices are used to measure the weight of biological cells or molecules  based on resonant frequency shifts experienced by the piezoelectric resonators.  Acoustic transducer use piezoelectric materials to generate sound waves that have been used in biological cell manipulation, such as cell focusing and sorting.