Polar Domains in Lead Titanate Films under Tensile Strain

Catalán, Gustau; Janssens, Arjen; Rispens, Gijsbert; Csiszar, S. I.; Seeck, O. H.; Rijnders, Guus; Blank, D. H. A.; Noheda, Beatriz

doi:10.1103/physrevlett.96.127602

Cited by 138 publications

(130 citation statements)

References 35 publications

Supporting

Mentioning

110

Contrasting

Order By: Relevance

“…A closer observation near the phase transitions reveals two noticeable changes in the signature of the Raman spectra: the disappearance of several stronger modes at ∼ 820 • C and the complete disappearance of all the modes above 1000 • C. This temperature behavior implies that BFO maintains its room temperature structure up to ∼ 820 • C, indicating the a structural (ferroelectric) phase transition, in agreement with the earlier investigations on BFO bulk single crystal and polycrystalline samples [24]. Note that thin films of BFO show first order phase transitions as in bulk, whereas STO and PbTiO 3 PTO are known to be first order in bulk but second order in thin films [25,26].…”

Section: Resultssupporting

confidence: 90%

Phonon spectroscopy near phase transition temperatures in multiferroicBiFeO3epitaxial thin films

2010

View full text Add to dashboard Cite

We report a Raman scattering investigation of multiferroic bismuth ferrite (BiFeO3) epitaxial (c-axis oriented) thin films from -192 to 1000 • C. Phonon anomalies have been observed in three temperature regions: in the γ-phase from 930 • C to 950 • C; at ∼ 370 • C, Néel temperature (TN), and at ∼ -123 • C, due to a phase transition of unknown type (magnetic or structural). An attempt has been made to understand the origin of the weak phonon-magnon coupling and the dynamics of the phase sequence. The disappearance of several Raman modes at ∼ 820 • C (Tc) is compatible with the known structural phase transition and the Pbnm orthoferrite space group assigned by Arnold et al. [1]. The spectra also revealed a non-cubic β-phase from 820-930 • C and the same non-cubic phase extends through the γ-phase between 930-950 • C, in agreement with Arnold et al. [2], and an evidence of a cubic δ-phase around 1000 • C in thin films that is not stable in powder and bulk. Such a cubic phase has been theoretically predicted in [3]. Micro-Raman scattering and X-ray diffraction showed no structural decomposition in thin films during the thermal cycling from 22-1000 • C.

show abstract

Section: Resultssupporting

confidence: 90%

Phonon spectroscopy near phase transition temperatures in multiferroicBiFeO3epitaxial thin films

2010

View full text Add to dashboard Cite

show abstract

“…With increasing film thickness, the effect of depolarization field becomes weaker and elastic strain energy increases and thus ferroelastic domains form to relax the strain energy. Such a domain structure transition from the depolarization field energydriven 180° domains to the elastic energy-driven 71° domains is further supported by a coexistence substrates, where 180° domains have been observed in ultrathin films (to compensate the large depolarization field) 26 and periodic c/a domain structures have been observed in relatively thicker films to compensate the increasing elastic energy. 44,45 As noted above, such domain structures can play an important role in the evolution of material…”

mentioning

confidence: 69%

180° Ferroelectric Stripe Nanodomains in BiFeO₃ Thin Films

Chen¹,

Liu²,

et al. 2015

Nano Lett.

View full text Add to dashboard Cite

show abstract

“…In dislocation-free epitaxial films, the strain is usually relieved by changing the system symmetry 23,24 or through the formation of ferroelastic domains 25 . Large flexoelectric polarizations have been reported for dislocation-free but ferroelastically twinned films with large elastic strain gradients causing a rotation of the polarization 21 ; in this case, the flexoelectric polarization were comparable to the spontaneous polarization of archetypal ferroelectrics evidencing that strain-engineered polar rotations can be an alternative pathway to enhancing piezoelectricity via the generation of ferroelectrics with tailored polarization 26,27 .…”

Section: Textmentioning

confidence: 99%

Polar-Graded Multiferroic SrMnO₃ Thin Films

et al. 2016

View full text Add to dashboard Cite

Engineering defects and strains in oxides provides a promising route for the quest of thin film materials with coexisting ferroic orders, multiferroics, with efficient magnetoelectric coupling at room temperature. Precise control of the strain gradient would enable custom tailoring of the multiferroic properties, but presently remains challenging. Here we explore the existence of a polar-graded state in epitaxially-strained antiferromagnetic SrMnO 3 thin films, whose polar nature was predicted theoretically, and recently demonstrated experimentally. By means of aberration-corrected scanning transmission electron microscopy we map the polar rotation of the ferroelectric polarization at atomic resolution, both far from and near the domain walls and find flexoelectricity resulting from vertical strain gradients. The origin of this particular strain state is a gradual distribution of oxygen vacancies across the film thickness, according to electron energy loss spectroscopy. Herein we present a chemistry-mediated route to induce polar rotations in oxygen-deficient multiferroic films, resulting in flexoelectric polar rotations and with potentially enhanced piezoelectricity. KEYWORDS: Multiferroics, ferroelectricity, flexoelectricity, aberration-corrected STEM, domain walls. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 4 TEXT Multiferroic materials have attracted great interest recently because of their intriguing fundamental physics and the wide range of potential applications such as transducers and information storage [1][2][3] . Of particular technological impact is the search for materials showing efficient coupling between ferromagnetic and ferroelectric orders that persist at room temperature. Manganese-based perovskite oxides AMnO 3 , A being an alkaline-earth cation, are particularly promising for this purpose; theoretical calculations reveal the onset of a ferroelectric ground state with strong magnetoelectric coupling since the spontaneous polarization is expected to be driven by the off-centering of the magnetic Mn 4+ ion 4,5 . The ferroelectric instability is predicted to increase by expansion of the lattice and, in turn, strain-induced ferroelectricity was experimentally demonstrated in Ba-substituted SrMnO 3 single crystals, in which chemical expansion of the crystal lattice is caused by partially replacing Sr with larger Ba ions 6 .Alternatively, strains can be induced into films through the use of epitaxial growth and can be utilized to modify the ferroelectric film properties by an adequate choice of the substrate 7-9 . In particular, strain-engineering of multiferroism has opened a path for the e...

show abstract

Polar Domains in Lead Titanate Films under Tensile Strain

Cited by 138 publications

References 35 publications

Phonon spectroscopy near phase transition temperatures in multiferroicBiFeO3epitaxial thin films

Phonon spectroscopy near phase transition temperatures in multiferroicBiFeO3epitaxial thin films

180° Ferroelectric Stripe Nanodomains in BiFeO₃ Thin Films

Polar-Graded Multiferroic SrMnO₃ Thin Films

Contact Info

Product

Resources

About

Polar Domains in Lead Titanate Films under Tensile Strain

Cited by 138 publications

References 35 publications

Phonon spectroscopy near phase transition temperatures in multiferroicBiFeO3epitaxial thin films

Phonon spectroscopy near phase transition temperatures in multiferroicBiFeO3epitaxial thin films

180° Ferroelectric Stripe Nanodomains in BiFeO3 Thin Films

Polar-Graded Multiferroic SrMnO3 Thin Films

Contact Info

Product

Resources

About

180° Ferroelectric Stripe Nanodomains in BiFeO₃ Thin Films

Polar-Graded Multiferroic SrMnO₃ Thin Films