Dynamics of the freezing process in relaxor ferroelectrics

Gui, Haoguan; Gu, Bing-Lin; Zhang, Xiaowen

doi:10.1103/physrevb.52.3135

Cited by 56 publications

(50 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Also, Monte Carlo computations performed for a twodimensional set of dipoles with random fields and random bonds gave a shallow dip in T m ͑E͒ until a threshold field above which T m started increasing. 20 These data emphasize the necessity of using the random-field-random-bond idea in order to explain the low-field dependence of T m in PMNxPT.…”

Section: ͑6͒mentioning

confidence: 90%

Bias-field effect on the temperature anomalies of dielectric permittivity inPbMg1∕3Nb2∕3

et al. 2005

View full text Add to dashboard Cite

In contrast to ordinary ferroelectrics where the temperature T m of the permittivity maximum monotonically increases with bias field E in ͑1−x͒PbMg 1/3 Nb 2/3 O 3 -͑x͒PbTiO 3 ͑0 ഛ x ഛ 0.35͒ single crystals, T m was found to remain constant or to decrease with E up to a certain threshold field E t , above which T m starts increasing. The threshold field E t decreases with increasing x, tending toward zero at approximately x = 0.4. We explain this dependence in the framework of models which take into account quenched random fields and random bonds. For crystals with 0.06ഛ x ഛ 0.13, the E-T phase diagrams are constructed. In contrast to PMN, they exhibit an additional, nearly field-independent boundary, in the vicinity of the Vogel-Fulcher temperature. We believe this boundary to correspond to an additional phase transition and the appearing order parameter is likely to be nonpolar.

show abstract

Section: ͑6͒mentioning

confidence: 90%

Bias-field effect on the temperature anomalies of dielectric permittivity inPbMg1∕3Nb2∕3

et al. 2005

View full text Add to dashboard Cite

show abstract

“…3 The time was measured in units of Monte Carlo steps per dipole ͑MCS/ dipole͒, which consists of 16ϫ16ϫ16 attempted flips. For relaxors, what is observed at low temperatures is the quasiequilibrium properties of a certain component in the phase space due to the ergodicity broken.…”

Section: ͑3͒mentioning

confidence: 99%

“…All these characteristics are consistent with the experiments 1 and the previous theoretical results. 3,22 The calculated susceptibility curves under different internal field widths e are depicted in Fig. 1͑a͒.…”

Section: ͑3͒mentioning

confidence: 99%

“…When the temperature is near T m , the proportion of fast dipoles varies rapidly with the temperature. 3,23 This means that some fast dipoles can be easily transformed into slow dipoles by the internal field. So the aging effect is more significant in this temperature region.…”

Section: ͑3͒mentioning

confidence: 99%

“…Various models, such as the dipolar glass model, the quenched random-field model, and the random-bandrandom-field model, have been proposed to account for the unusual physical properties of relaxor ferroelectrics. [2][3][4][5][6] The relatively high dielectric constant and lowtemperature coefficient has led to many successful applications of relaxors such as multilayered capacitors. Due to their influences on the actual applications and the comprehension of the dielectric mechanism, the dielectric aging behaviors of relaxor ferroelectrics have been extensively investigated in the last decade.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Effect of defect-induced internal field on the aging of relaxors

Duan

Wang

et al. 2003

Phys. Rev. B

View full text Add to dashboard Cite

The effect of a defect-induced internal field on the dielectric response of relaxor ferroelectrics is investigated using a Monte Carlo simulation. It was observed that only at a small temperature range near the temperature of the dielectric maximum does the susceptibility decrease markedly due to the internal field. This temperature range increases with enhancing internal field. We found that the susceptibility is almost independent of the internal field width at low internal field width, and then decreases linearly with enhancing internal field width. This dependence of the susceptibility on the internal field width is very similar to the relation of the dielectric constant with logarithmic aging time, which probably suggests a linear dependence of the internal field on the logarithm of the aging time. The frequency dependence of the susceptibility aging is sensitive to the temperature. With increasing temperature, the curve of the susceptibility change against logarithmic frequency varies from concave to approximately linear, and then to convex, which is in agreement with the recent aging rate measurement. Relaxor ferroelectrics ͑relaxors͒ have special dielectric characteristics compared with normal ferroelectrics. A typical relaxor ferroelectric displays a diffuse phase transition, a strong frequency dispersion of the dielectric properties, and an absence of macroscopic polarization at zero electric field. 1 Although the origin of these dielectric features is still controversial, it has been suggested that the presence of polar microregions in nanoscale is crucial to the relaxor behaviors. Various models, such as the dipolar glass model, the quenched random-field model, and the random-bandrandom-field model, have been proposed to account for the unusual physical properties of relaxor ferroelectrics. [2][3][4][5][6] The relatively high dielectric constant and lowtemperature coefficient has led to many successful applications of relaxors such as multilayered capacitors. Due to their influences on the actual applications and the comprehension of the dielectric mechanism, the dielectric aging behaviors of relaxor ferroelectrics have been extensively investigated in the last decade. 7-14 The experimental results have indicated the importance of the defect structure in the aging in this type of material. For example, very little dielectric aging was observed for a carefully prepared pure PMN. However, PMN with Mn and other acceptor dopants shows significant aging. 10 The main characteristic of acceptor dopants is the introduction of O 2Ϫ vacancies, which results in the formation of the oxygen-vacancy-metal-impurity defect dipoles. 7,8 The reorientation and alignment of the defect dipoles with the local nanoscale polar domains lead to the internal field, which provides a pinning to the polar microregion and results in a decrease of the switchable polarization. 15,16 It is widely accepted nowadays that the defect-induced internal field is responsible for the aging behavior in relaxor ferroelectrics, but how the inter...

show abstract

Effect of the surroundings on the photophysical properties of CsPbBr₃ perovskite quantum dots embedded in SiO_x matrices

Lee

Seo

et al. 2022

Bulletin Korean Chem Soc

View full text Add to dashboard Cite

Organometallic lead halide perovskites have been studied extensively owing to their excellent photophysical properties and have been successfully applied to solar-driven chemistry and optoelectronic devices. Dimensionally confined perovskite quantum dots (PQDs) have demonstrated outstanding photoluminescence quantum yields, detailed band gap tunability, wide color gamut, and favorable radiative recombination processes. These characteristics expand the versatility of PQDs. Various efforts have been made to increase their stability. The introduction of a core-shell structure increased the stability of PQDs, and they were successfully applied to light-emitting diodes. Recently, our group demonstrated the potential of PQDs to promote photocatalytic degradation of carcinogens. However, further studies on the detailed interactions between PQDs and their surroundings are necessary to utilize them in practice. This study investigated the impact of surrounding solvents on the material/photophysical properties of PQDs and statistically observed the photoinduced charge transfer from PQDs to transparent conducting oxides. The findings of this study could be used to advance solar-driven chemistry and optoelectronic devices and to promote the utilization of PQDs in renewable energy applications.K E Y W O R D S core-shell perovskite quantum dot, perovskite quantum dot, photoinduced charge transfer, time-resolved spectroscopy

show abstract

Dynamics of the freezing process in relaxor ferroelectrics

Cited by 56 publications

References 27 publications

Bias-field effect on the temperature anomalies of dielectric permittivity inPbMg1∕3Nb2∕3

Bias-field effect on the temperature anomalies of dielectric permittivity inPbMg1∕3Nb2∕3

Effect of defect-induced internal field on the aging of relaxors

Effect of the surroundings on the photophysical properties of CsPbBr₃ perovskite quantum dots embedded in SiO_x matrices

Contact Info

Product

Resources

About

Dynamics of the freezing process in relaxor ferroelectrics

Cited by 56 publications

References 27 publications

Bias-field effect on the temperature anomalies of dielectric permittivity inPbMg1∕3Nb2∕3

Bias-field effect on the temperature anomalies of dielectric permittivity inPbMg1∕3Nb2∕3

Effect of defect-induced internal field on the aging of relaxors

Effect of the surroundings on the photophysical properties of CsPbBr3 perovskite quantum dots embedded in SiOx matrices

Contact Info

Product

Resources

About

Effect of the surroundings on the photophysical properties of CsPbBr₃ perovskite quantum dots embedded in SiO_x matrices