Some experimental investigations of electromechanical properties of (PbZn_(1/3)Nb_(2/3)O_3)0.92-(PbTiO_3)0.08 relaxor single crystals

摘要

The present paper deals with some electromechanical properties of the relaxor-type ferroelectric (PbZn_(1/3)Nb_(2/3)O_3)0.92-(PbTiO_3)0.08 single crystal. The cube samples with faces oriented in the [100]_c direction, and the plates with major plane oriented in the [100]_c direction were measured. Using the low-field dynamic (resonant) and high-field static methods we have measured the set of material characteristics: piezoelectric coefficients d_(33), electromechanical coupling coefficient k_(31), and elastic coefficients s_(λ μ)~E. In addition, the piezoelectric coefficient d_(31) was studied in more detail; in particular, its temperature dependence was determined in the range 200-330 K. Data on displacement vs. electric field dependence in this temperature range have been obtained using a new double beam interferometer and optical helium cryostat. The main problem of such measurements, namely the suppression of cooling system vibrations as a necessary condition for the measurements, was solved by a new method [Ann. Chim. Sci. Mater. 26 (2001) 43-48].