Three intrinsic relationships of lattice parameters between intermediate monoclinic<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi mathvariant="normal">M</mml:mi><mml:mi mathvariant="normal">C</mml:mi></mml:msub></mml:math>and tetragonal phases in ferroelectric<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">Pb</mml:mi><mml:mrow><mml:mo>[</mml:mo><mml:msub><mml:mrow><mml:mo>(</mml:mo><mml:msub><mml:m

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The piezoelectric response of ͓001͔ poled domain engineered ͑1−x͒Pb͑Mg 1/3 Nb 2/3 ͒O 3 − xPbTiO 3 ͑PMN-PT͒ crystals was investigated as a function of composition and phase using Rayleigh analysis. The results revealed that the intrinsic ͑reversible͒ contribution plays a dominant role in the high piezoelectric activity for PMN-PT crystals. The intrinsic piezoelectric response of the monoclinic ͑M C ͒ PMN− xPT crystals, 0.31Յ x Յ 0.35, exhibited peak values for compositions close to R-M C and M C -T phase boundaries, however, being less than 2000 pC/N. In the rhombohedral phase region, x Յ 0.30, the intrinsic piezoelectric response was found to increase as the composition approached the rhombohedral-monoclinic ͑R-M C ͒ phase boundary. The maximum piezoelectric response was observed in rhombohedral PMN-0.30PT crystals, being on the order of 2500 pC/N. This ultrahigh piezoelectric response was determined to be related to the high shear piezoelectric activity of single domain state, corresponding to an ease in polarization rotation, for compositions close to a morphotropic phase boundary ͑MPB͒. The role of monoclinic phase is only to form a MPB with R phase, but not directly contribute to the ultrahigh piezoelectric activity in rhombohedral PMN-0.30PT crystals. The extrinsic contribution to piezoelectric activity was found to be less than 5% for the compositions away from R-M C and M C -T phase boundaries, due to a stable domain engineered structure. As the composition approached MPBs, the extrinsic contribution increased slightly ͑Ͻ10%͒, due to the enhanced motion of phase boundaries.

mentioning

confidence: 65%

Composition and phase dependence of the intrinsic and extrinsic piezoelectric activity of domain engineered (1−x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 crystals

Zhang

Wang

et al. 2010

214

160

“…Other types of stacking defects, such as twin boundaries, are known in ferromagnetic ͑magnetostrictive͒ and ferroelectric ͑piezoelectric͒ perovskite oxides. [21][22][23][24][25][26] In magnetostrictive oxides with high Néel temperatures ͑such as CFO͒, such twin boundaries could readily form in epitaxial thin layers during crystallization, annealing, or thermal treatments.…”

Section: Introductionmentioning

confidence: 99%

Nanogrowth twins and abnormal magnetic behavior in CoFe2O4 epitaxial thin films

Wang

et al. 2008

Nanogrowth twins (GTs) have been observed in CoFe2O4 (CFO) epitaxial thin films deposited on (111) oriented SrTiO3 substrates by pulsed laser deposition. The GTs form during nucleation and growth and consist of CFO growth regions that have a mirror relationship with respect to each other. We show that the films with GTs (i) are better crystallized than the ones without them and (ii) have higher saturation magnetizations due to the presence of twin boundaries.

“…Moreover, the small size of nanotwins gives rise to high density of twin boundaries, which makes material more deformable as twin boundaries can accommodate the macroscopic strain, induced by external electric field or applied stress. 61 The rearrangement of nanotwins with symmetry lower than the macroscopic symmetry results in giant strain and enhanced piezoelectric response under applied fields. 62 Furthermore, we believe that higher mobility of these nano twins is responsible for giving rise to high strain energy density in MPB composition of NBT-BT.…”

Section: Resultsmentioning

confidence: 99%

Origin of high piezoelectric response in A-site disordered morphotropic phase boundary composition of lead-free piezoelectric 0.93(Na0.5Bi0.5)TiO3–0.07BaTiO3

Maurya

Murayama

Pramanick

et al. 2013