Anomalous broad dielectric relaxation in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Bi</mml:mi></mml:mrow><mml:mrow><mml:mn>1.5</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Zn</mml:mi></mml:mrow><mml:mrow><mml:mn>1.0</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Nb</mml:mi></mml:mrow><mml:mrow><mml:mn>1.5</mml:m

Kamba, S.; Porokhonskyy, V.; Pashkin, Alexej; Bovtun, V.; Petzelt, J.; Nino, Juan C.; Trolier‐McKinstry, Susan; Lanagan, Michael T.; Randall, Clive A.

doi:10.1103/physrevb.66.054106

Cited by 208 publications

(137 citation statements)

References 32 publications

Supporting

Mentioning

115

Contrasting

Unclassified

Order By: Relevance

“…If we assume that the Pb cations and some of the oxygen anions are dynamically disordered among more equivalent positions with the avarage structure remaining cubic like in isostructural Bi 1.5 ZnNb 1.5 O 7 , 22 , then 14 modes could be IR active, 23 close to our experimental result. The problem with the excess IR active modes is also known from the perovskite PMN , where only 4F 1u polar modes are allowed in F m3m structure, although 7 modes were observed.…”

Section: Resultssupporting

confidence: 77%

Quantum paraelectric behavior of pyrochlorePb1.83Mg0.29Nb1.71O6.39

Kamba¹,

Денисов²,

Veljko³

et al. 2007

Phys. Rev. B

View full text Add to dashboard Cite

Pb1.83Mg0.29Nb1.71O6.39 (PMN) crystallizing in a cubic pyrochlore structure exhibits, as the first dielectrics with pyrochlore structure, typical feature of quantum paraelectrics -its permittivity continuously increases on cooling and levels off below ∼ 30 K without any signature of a structural phase transition. Broad-band dielectric spectra do not show any dielectric dispersion in the real part of permittivity up to 8.8 GHz. THz and infrared spectra reveal a soft polar optic mode which is responsible for the temperature dependence of the permittivity. The leveling-off of the permittivity at low temperatures obeys the Barrett formula and the fitted vibrational zero-point energy 1 2 kBT1 corresponds to the measured soft mode frequency. The number of observed infrared phonons exceeds that predicted from the factor-group analysis which indicates that the structure is at least locally non-cubic.

show abstract

Section: Resultssupporting

confidence: 77%

Quantum paraelectric behavior of pyrochlorePb1.83Mg0.29Nb1.71O6.39

Kamba¹,

Денисов²,

Veljko³

et al. 2007

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…On the other hand, in the dilute limit, the concentration of defects then increases as a function of temperature (Kohan et al, 2000), which probably leads to an increase in the total number of defect-induced dipole moments and consequently to changes in the dielectric constant. This coincides with the trend observed in the dielectric-temperature spectra of BZN (Kamba et al, 2002). Volanti et al (Volanti et al, 2007) …”

Section: 'Non-stoichiometry' and The Nature Of Defects In Bzn (Liu Etsupporting

confidence: 75%

“…Such behaviour is indicative of displacive motion requiring thermally activated hopping over a potential barrier, which then freezes out at a sufficiently low temperature. The frequency dependence of the peak position in the dielectric loss curve (see Fig.4), following a previous approach (Kamba et al, 2002;Nino et al, 2001), can in general be modelled using either the basic Arrhenius type equation…”

Section: Average Structure and Dielectric Properties Of Bi-based Niobmentioning

confidence: 99%

Local Structure of Relaxor Dielectric Ceramics

Liu¹,

Withers²

2011

Advances in Ceramics - Electric and Magnetic Ceramics, Bioceramics, Ceramics and Environment

View full text Add to dashboard Cite

“…This disorder is expected to be an important ingredient in the physics of BZN since the dielectric properties are believed to be closely associated with the A 2 O 0 network [13].…”

Section: Introductionmentioning

confidence: 99%

Displacive disorder in three high-k bismuth oxide pyrochlores

Melot

Rodriguez

Proffen

et al. 2006

Materials Research Bulletin

View full text Add to dashboard Cite

We use time-of-flight neutron powder diffraction to examine static displacive disorder in three different pyrochlore A 2 B 2 O 6 O 0 compounds with Bi on the A site. The compounds (Bi 1.5 Zn 0.5 )(Nb 1.5 Zn 0.5 )O 6 O 0 (BZN), (Bi 1.5 Zn 0.5 )(Ta 1.5 Zn 0.5 )O 6 O 0 (BZT), and (Bi 1.5 Zn 0.5 )(Sb 1.5 Zn 0.5 )O 6 O 0 (BZS), are of interest -particularly BZN -for their high dielectric constants in the absence of any phase transition from the cubic high temperature phase. The local structures of the three compounds is characterized by displacive disorder from the ideal pyrochlore positions for both the A and O 0 sites, with the precise nature of the disorder being quite similar. However the extent of displacive disorder is different, despite the B-O networks being nearly identical in the three compounds. The reported dielectric constants of the three compounds are related to the extent of local displacement, and BZN, with the largest extent of local atomic displacement of A and O 0 , is also reported to have the largest dielectric constant at 1 MHz. The dielectric constants are also related to the magnitudes of the thermal parameters of the different ions. The strongest correlation is found to involve the thermal parameter on the B site (Nb, Ta, or Sb). #

show abstract

Anomalous broad dielectric relaxation inBi1.5Zn1.0Nb1.5

Cited by 208 publications

References 32 publications

Quantum paraelectric behavior of pyrochlorePb1.83Mg0.29Nb1.71O6.39

Quantum paraelectric behavior of pyrochlorePb1.83Mg0.29Nb1.71O6.39

Local Structure of Relaxor Dielectric Ceramics

Displacive disorder in three high-k bismuth oxide pyrochlores

Contact Info

Product

Resources

About