Breakthrough in Piezoelectric Imaging Could Lead to Cell-Sized Motors

Achievement date: 
2018
Outcome/accomplishment: 

An intercollegiate research team at the NSF-funded Engineering Research Center (ERC) for Translational Applications of Nanoscale Multiferroic Systems (TANMS), headquartered at the University of California, Los Angeles (UCLA), has demonstrated direct imaging of nanoscale strain variations on a single crystal piezoelectric sample for the first time.

Impact/benefits: 

The coupling of electric polarization and mechanical strain differentiates piezoelectric crystals from a broader set of electrostrictive materials, the latter of which do not necessarily exhibit behavior dependent on electrical polarity. Nanoscale measurement of single crystal piezoelectric behavior under varying electrical fields represents a fundamental contribution to nanoscale control of multiferroic materials.

Explanation/Background: 

When a piezoelectric crystal is electrically charged, it responds by changing shape. This effect in itself is a property of all electrostrictive materials. What makes piezoelectric crystals unique is that the polarity of the electrical charge causes them to be strained differently. The latter effect can be combined with magnetostrictive materials to convert that strain to magnetic energy with the polarity of the electrical charge altering magnetic domains spins.

Imaging the strain of a single piezoelectric crystal offers critical insight into being able to control the magnetism of multiferroic materials at that scale. The knowledge begotten by this research can lead to the creation of extremely small multiferroic motors on the order of human blood cells, of which one of many applications is delivering precision treatments for cancer and other diseases.