Pyroelectric properties of (1−x)Pb(Mg1∕3Nb2∕3)O3-xPbTiO3 and (1−x)Pb(Zn1∕3Nb2∕3)O3-xPbTiO3 single crystals measured using a dynamic method

Abstract

The pyroelectric coefficients of 0.72Pb(Mg1∕3Nb2∕3)O3-0.28PbTiO3 (PMN-28PT), 0.67Pb(Mg1∕3Nb2∕3)O3-0.33PbTiO3 (PMN-33PT), and 0.92Pb(Zn1∕3Nb2∕3)O3-0.08PbTiO3 (PZN-8PT) single crystals, oriented and poled along three different crystallographic directions, [001]C, [011]C, and [111]C, have been measured using a dynamic method. The suffix C indicates reference to the prototypic cubic coordinate system. Large coefficients of up to 1070μCm−2K−1 have been observed for the [111]C oriented, rhombohedral PMN-28PT and PMN-33PT samples, where the measurement direction corresponds to the polar axis of the crystal. For each composition and orientation two different poling procedures are compared, a commonly used field cooling method and a low temperature poling protocol. It was found that in otherwise pseudoorthorhombic samples of PZN-8PT, a room temperature rhombohedral phase could be stabilized by application of a field along the [111]C direction while heating from −70°C.

Picturing the elephant: Giant piezoelectric activity and the monoclinic phases of relaxor-ferroelectric single crystals

“…Furthermore, again as noted in Section 1, the zero-field phase present after poling and its range of thermal stability can depend upon the orientation of the applied poling field [22,51,53,54,143,145,150]. The importance of this result will be returned to in the Section 3.…”

“…In pre-poled samples, the initial phase is usually recovered after removal of the field. In unpoled samples, irreversible electric-field induced transitions can occur [51,131], including from a short-range ordered state for samples that are not spontaneously ferroelectric [47].…”

“…However, poling using different poling protocols (e.g. field cooling), at different temperatures and differing electric field levels can often alter the resultant zero-field phase [22,51,52]. Furthermore, poling by field cooling can induce different phases in differently-oriented crystals; for example, [001] C -poled PMN-35PT has been shown to be monoclinic whereas [101] C -poled PMN-35PT is orthorhombic [53,54].…”

“…Therefore, we might refer to such M C "phases" as "pseudo-orthorhombic [22,51,151]," unless of course they become "pseudo-tetragonal" in their other limit (see Fig. 4).…”

Achieving single domain relaxor-PT crystals by high temperature poling

“…2,13,14 From the application viewpoint, on the other hand, single domain crystals exhibit many advantages, such as high thickness shear piezoelectric and pyroelectric properties. [15][16][17][18][19][20][21] As given in Table 1 To obtain domain engineered configurations, the ferroelectric crystals are poled along specific non-polar directions, so various domains appear in the crystals. These domains can form various non-180°domain configurations, satisfying the mechanical compatibility to minimize the strain energy.…”