High-accuracy characterization of pyroelectric materials:A noncontact method based on surface potential measurements

The characterization of pyroelectric materials is essential for the design of pyroelectric-based devices.Pyroelectric current measurement is the commonly employed method,but can be complex and requires surface electrodes.Here,we present noncontact electrostatic voltmeter measurements as a simple but highly accurate alternative,by assessing thermally-induced pyroelectric surface potential variations.We introduce a refined model that relates the surface potential variations to both the pyroelectric coefficient and the characteristic figure of merit(FOM)and test the model with square-shaped samples made from PVDF,LiNbO3 and LiTaO3.The characteristic pyroelectric coefficient for PVDF,LiNbO3 and LiTaO3 was found to be 33.4,59.9 and 208.4μC m−2 K−1,respectively.These values are in perfect agreement with literature values,and they differ by less than 2.5%from values that we have obtained with standard pyroelectric current measurements for comparison.