Electric polarization is measured by pyro-current technique.
The charge induced on the sample faces generates current IP via a probe resistor. The current is recorded by a digitizer, and integrated numerically to obtain electric polarization P.
The sample should be shaped as a plane-parallel plate, with a surface area of few square millimeters, and thickness 0.1 – 1 mm. The polling voltage ranges +/- 500 V.
Magnetic-field variation of the pyrocurrent and the electric polarization for the two axes of the CuO single crystal.