Search results for "Burns temperature"

showing 7 items of 7 documents

<title>Correlation effects in the disordered ferroelectrics</title>

2003

ABSTRACT The calculation of the correlation radius distribution function is performed for the cases of undamped and overdamped softmode dispersion laws. Taking into account the correlation radius dependence on the random field and this field distribution function we carried out the theoretical calculation of the correlation radius distribution function dependence ontemperature, damping coefficient and random field distribution function parameters. It was shown that at temperaturehigher than Burns temperature Td the most probable value of the correlation radius is equal to its maximal valueindependently on the system disorder, while in the dipole glass state it is close to the minimal value …

Correlation function (statistical mechanics)DipoleRandom fieldDistribution functionField (physics)Condensed matter physicsChemistryRadiusPolarization (waves)Burns temperatureSPIE Proceedings
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Polar phonons in relaxor ferroelectric 0.2PSN-0.4PMN-0.4PZN

2008

Relaxor ferroelectrics 0-2PbSc(1/2)Nb(1/2)O(3) - 0.4PbMg(1/3)Nb(2/3)O(3)-0.4PbZn(1/3)Nb(2/3)O(3) ceramics were studied by means of the Fourier transform infrared reflection and THz transmission spectroscopy in the temperature range of 20-500 K. On heating from low temperatures, the A(1) component of the strongly split TO1 mode softens towards the Burns temperature, but the softening ceases near 400 K, which could be a signature of polar cluster percolation temperature.

Materials scienceCondensed matter physicsPhononInfraredGeneral Physics and AstronomyAtmospheric temperature rangesymbols.namesakeFourier transformReflection (mathematics)visual_artPercolationsymbolsvisual_art.visual_art_mediumCeramicBurns temperature
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Far-infrared and THz spectroscopy of 0.4PMN–0.3PSN–0.3PZN relaxor ferroelectric ceramics

2007

Abstract Temperature dependence of the optic phonons in 0.4PbMg 1/3 Nb 2/3 O 3 –0.3PbSc 1/2 Nb 1/2 O 3 –0.3PbZn 1/3 Nb 2/3 O 3 (0.4PMN–0.3PSN–0.3PZN) ceramics were studied by means of FTIR reflection and THz transmission spectroscopy in the temperature range of −253.15 to 226.85 °C. On heating from low temperatures, the A 1 component of the strongly split TO 1 mode softens towards the Burns temperature, but the softening ceases near 126.85 °C which could be a signature of polar cluster percolation temperature. Surprisingly, the TO 2 mode also softens on heating and follows the Cochran law with extrapolated critical temperature close to the melting point.

Materials scienceCondensed matter physicsPhononMineralogyAtmospheric temperature rangeFar infraredvisual_artPercolationMaterials ChemistryCeramics and CompositesMelting pointvisual_art.visual_art_mediumCeramicSpectroscopyBurns temperatureJournal of the European Ceramic Society
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High Temperature Dielectric Properties of PMN‐PSN‐PZN Relaxors

2019

Materials scienceDielectricComposite materialCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsBurns temperaturephysica status solidi (b)
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Thermal Expansion, Burns Temperature and Electromechanical Properties in Na1/2Bi1/2TiO3-SrTiO3-PbTiO3Solid Solutions

2011

Thermal expansion and electromechanical properties are studied for compositions Na1/2Bi1/2TiO3-SrTiO3-PbTiO3, belonging to various locations in the phase diagram. The main purpose of the studies is to extend the range of physical properties, which characterise the relaxor state and could be used for comparison with other relaxors. Possibility to evaluate Burns temperature from thermal expansion is discussed. The obtained results are compared to the well-know relaxor ferroelectric PLZT.

Materials scienceThermodynamicsCondensed Matter PhysicsThermal expansionElectronic Optical and Magnetic MaterialsBurns temperatureRelaxor ferroelectricSolid solutionPhase diagramFerroelectrics
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Distribution of the relaxation times of the new relaxor 0.4PSN–0.3PMN–0.3PZN ceramics

2005

Abstract The real distribution function of the relaxation times g ( τ ) of the relaxor ferroelectric ceramics 0.4PSN–0.3PMN–0.3PZN is calculated from the experimental dielectric spectra obtained in the frequency range from 20 Hz to 1.25 GHz. Below the Burns temperature T B  ≅ 380 K, where the clusters begin to appear on cooling, the distribution of the relaxation times is symmetrically shaped. On cooling, the permittivity and loss spectra strongly broaden and slow down. The g ( τ ) function becomes asymmetrically shaped and the second maximum appears. The width of the g ( τ ) function is calculated at different temperatures. The shortest relaxation time is of the order of 10 −12  s and it r…

PermittivityMaterials scienceDistribution functionCondensed matter physicsDistribution (number theory)Relaxation (NMR)Inorganic chemistryMaterials ChemistryCeramics and CompositesRange (statistics)Function (mathematics)Spectral lineBurns temperatureJournal of the European Ceramic Society
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Infrared and broadband dielectric spectroscopy of PZN-PMN-PSN relaxor ferroelectrics: Origin of two-component relaxation

2006

Dielectric spectra of several solid solutions of $\mathrm{Pb}{\mathrm{Mg}}_{1∕3}{\mathrm{Nb}}_{2∕3}{\mathrm{O}}_{3}\text{\ensuremath{-}}\mathrm{Pb}{\mathrm{Sc}}_{1∕2}{\mathrm{Nb}}_{1∕2}{\mathrm{O}}_{3}\text{\ensuremath{-}}\mathrm{Pb}{\mathrm{Zn}}_{1∕3}{\mathrm{Nb}}_{2∕3}{\mathrm{O}}_{3}$ (PMN-PSN-PZN) relaxor ferroelectrics were investigated in a broad frequency range from $20\phantom{\rule{0.3em}{0ex}}\mathrm{Hz}$ up to $100\phantom{\rule{0.3em}{0ex}}\mathrm{THz}$ by a combination of dielectric spectroscopy $(20\phantom{\rule{0.3em}{0ex}}\mathrm{Hz}\char21{}53\phantom{\rule{0.3em}{0ex}}\mathrm{GHz})$, time-domain terahertz spectroscopy $(0.1\char21{}0.9\phantom{\rule{0.3em}{0ex}}\mathrm{TH…

PhysicsDielectric spectrumCondensed matter physicsPhononInfraredInfrared spectroscopyDielectricCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsBroadband dielectric spectroscopyBurns temperatureSolid solutionPhysical Review B
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