Abstract
Two types of electrodes, sputtered Au/Ti and fired Ag, were applied to Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3 (PZNT91/9) single crystals and showed the results obtained below. These results suggest at a new method for controlling the domain structure and electrical properties of these crystals.
(1) The dielectric constant K at room temperature is 8000 for Au/Ti electrode samples. However, samples with fired Ag electrodes indicate the lower K value of 1000.
(2) The dielectric constant Kmax at the Curie temperature is almost the same for both types of electrodes.
(3) After electrical poling, Au/Ti samples indicate an electromechanical coupling coefficient kt of 52.7%, while samples with fired Ag electrodes have a relatively high kt value of 61.4%.
(4) The lower dielectric constant in the case of the fired Ag electrodes may be due to mechanical poling. This phenomenon increases the mechanical coupling factor kt of poled single crystals.
