1. Ultrasound

In 1880, Pierre and Jacques Curie discovered the direct piezoelectric effect by observing the electrical polarization of a quartz sample subjected to mechanical stress. The inverse effect, established by Lippman in 1881, creates a mechanical vibration from alternating electrical energy. This discovery led Langevin to develop sonar, the first known application of ultrasound. In the second half of the twentieth century, this technology experienced its most remarkable boom with the industrial development of ultrasonic cleaning. This evolution continued with the emergence of sonochemistry and the numerous research projects it encompassed, opening up the prospect of new applications for ultrasonic waves.