Probing the effect of ferroelectric to paraelectric phase transition on the Ti-3d and O-2p hybridization in BaTiO3

Abstract

We report the modifications in the electronic properties of single phase polycrystalline BaTiO3 due to ferroelectric to paraelectric phase transition revealed by temperature dependent synchrotron based x-ray absorption and valence band spectroscopy. Valence band spectra show a strong temperature dependence of Ti-3d and O-2p hybridized states around the phase transition. It is observed that Ti-O hybridization is stronger in the paraelectric phase, which is also supported by multiplet calculations at the Ti L-edge. We also find a reduced crystal field value in the paraelectric phase than in the ferroelectric phase, which is caused by volume expansion and a reduction in tetragonal distortion.

Structural correlations in the enhancement of ferroelectric property of Sr doped BaTiO3

“…However, the transitions are shifted towards lower temperature as compared to BTO, which is consistent with earlier work [23]. Interestingly, the value of dielectric constant at cubic to tetragonal transition is around 7000 at 5 kHz which is much higher than the pure BTO [24] and tan value is also less. This shows that the dielectric constant is enhanced for 20% Sr doped sample.…”

Synthesis and Characterization of Vertically Aligned La0.7Sr0.3MnO3:NiO Nanocomposite Thin Films for Spintronic Applications

“…Feature B is highly sensitive to the valence of Mn and strain. The broad bands represented by C and D are attributed to O-2p-derived states hybridized with La-5d/Sr-4f and Mn-4sp, respectively. ,, …”

“…The broad bands represented by C and D are attributed to O-2p-derived states hybridized with La-5d/Sr-4f and Mn-4sp, respectively. 53,58,59 Here, we have focused on the feature A (A1 as e g ↑ and A2 as t 2g ↓) and feature B (e g ↓) because these features carry the main information about the hybridization between Mn/Ni 3d with O 2p states. We have fitted the spectra with the combination of an arctan function as background and a series of Gaussian peaks 59 by using the software Athena.…”

“…53,58,59 Here, we have focused on the feature A (A1 as e g ↑ and A2 as t 2g ↓) and feature B (e g ↓) because these features carry the main information about the hybridization between Mn/Ni 3d with O 2p states. We have fitted the spectra with the combination of an arctan function as background and a series of Gaussian peaks 59 by using the software Athena. These e g and t 2g features are distinctly visible after fitting the feature A (A1 as e g ↑ and A2 as t 2g ↓) and B (e g ↓).…”

Electrical fatigue behavior of Ba0.85Ca0.15Zr0.1Ti0.9O3 ceramics under different oxygen concentrations

“…The XANES spectra peak intensities and their corresponding changes are listed in Table-2. Peaks A and B are attributed to electron transition from O 1s orbital to O 2p-Ti 3d derived orbital (t2g and eg) states[46][47][48].Peak C1 and C2 are attributed to electron transition from O 1s orbital to O2p-Ca 3d/Ba 5d derived hybrid states[49]. Peak D1 and D2 are attributed to the influence of the empty Ba-5f band on O-2p states[45].…”