Coexistence of ferroelectric and relaxor properties in epitaxial films of Ba1−xSrxTiO3

Evidence for Strain-Induced Ferroelectric Order in Epitaxial Thin-FilmKTaO3

“…Importantly, in epitaxial films of perovskite-type relaxors, strain has been found to enhance relaxor features, but not to induce the FE state [11]. Unexpectedly, the relaxorlike properties have been observed also in epitaxial films of FE BaTiO 3 and FE ðBa; SrÞTiO 3 [12,13].…”

“…In BaTiO 3 films, the FE order has been demonstrated for s ¼ À2:1% [8], s ¼ À1:3% [7], and s ¼ 0:58% [27], with the relaxorlike properties found for s ¼ À0:7%-0% [12]. The relaxorlike properties evidenced in epitaxial films of ðBa; SrÞTiO 3 [13] indicate a presence of the short-range-order region in the phase diagram for this FE, too. Similar short-range order found in epitaxial films grown by different methods and in different laboratories [9,12,13] suggests its fundamental origin, not related to technological imperfections.…”

“…The relaxorlike properties evidenced in epitaxial films of ðBa; SrÞTiO 3 [13] indicate a presence of the short-range-order region in the phase diagram for this FE, too. Similar short-range order found in epitaxial films grown by different methods and in different laboratories [9,12,13] suggests its fundamental origin, not related to technological imperfections. Studies of dynamic effects might give a clue to understanding this origin [12,28].…”

Epitaxial Integration of Ferroelectric BaTiO3 with Semiconductor Si: From a Structure- Property Correlation Point of View

“…The relatively high value of 1.624 also indicates a relaxor behavior, which seems to be inconsistent with the predominant concept that BTO is a typical displacive ferroelectric material and should exhibit sharp dielectric transition [92]. However, recent nuclear magnetic resonance and Raman scattering studies had both evidenced the coexistence of the displacive character of transverse optical soft mode with the order-disorder character of Ti ions [93], especially in the BTO thin films. As the sputtering is proceed in an oxygen deficient atmosphere, thus the oxygen vacancies induced structural disorders and compositional fluctuations in the film may be responsible for the observed relaxor behavior.…”

Microstructure and dielectric relaxor properties for Ba0.5Sr0.5TiO3/La0.67Sr0.33MnO3 heterostructure

“…4 shows the Curie-Weiss plots ͓ ͑T͒ −1 against T͔ deduced from ͑E=0͒ vs T. By fitting the experimental data, the Curie-Weiss constant is estimated as 2.23ϫ 10 5 K, which agrees well with other values of BST films of the displacive type. 23 For comparison, the Curie-Weiss constant of the order-disorder type ferroelectric has small values in the range of 10 2 -10 3 K. 24 For practical application, the dielectric tunability should be as large as desired. The dielectric tunability is defined as…”