Hysteresis loop of the ceramic is measured by Sawyer-Tower circuit shown in
Fig.1 . A sinusoidal field of Vrms and 50 Hz is applied to the sample with fixed C0.
The voltage across the ceramic (Cs) is recorded on the horizontal axis (X-axis) of the
oscilloscope, while the voltage across the capacitor (C0), which is proportional to the
polarization on the sample Cs, is recorded on the vertical axis (Y-axis) of the
oscilloscope. The measurement is carried out at room temperature.