Mumbai university > FE > SEM 1 > Applied Physics 1

Marks: 3M

Year: Dec 2013

• The piezoelectric crystals are electrically neutral containing equal number of positive and negative ions.

• Fig 8.1 shows the simple arrangement of ions in a piezoelectric crystal.

• The centroids of both positive and negative crystals are at the same point, i.e. in the center.

• When an external pressure is applied along Y-axis (Fig. 8.2), the Crystal gets deformed along X-direction as shown.

• As a result, the centroids of the positive and negative ions move away from each other, developing a small potential difference along X-axis.

• In this way, a potential difference can be developed in a piezoelectric crystal by applying pressure.

• This phenomenon is called Inverse-Piezoelectric effect.