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Luo J.,TRS Technologies | Zhang S.,Pennsylvania State University
Crystals | Year: 2014

Compared to Pb(Zr1-xTix)O3(PZT) polycrystalline ceramics, relaxor-PT single crystals offer significantly improved performance with extremely high electromechanical coupling and piezoelectric coefficients, making them promising materials for piezoelectric transducers, sensors and actuators. The recent advances in crystal growth and characterization of relaxor-PT-based ferroelectric single crystals are reviewed in this paper with emphases on the following topics: (1) the large crystal growth of binary and ternary relaxor-PT-based ferroelectric crystals for commercialization; (2) the composition segregation in the crystals grown from such a solid-solution system and possible solutions to reduce it; (3) the crystal growth from new binary and ternary compositions to expand the operating temperature and electric field; (4) the crystallographic orientation dependence and anisotropic behaviors of relaxor-PT-based ferroelectriccrystals; and (5) the characterization of the dielectric, elastic and piezoelectric properties of the relaxor-PT-based ferroelectriccrystals under small and large electric fields. © 2014 by the authors; licensee MDPI, Basel, Switzerland. Source

Lee H.J.,Pennsylvania State University | Zhang S.,Pennsylvania State University | Luo J.,TRS Technologies | Li F.,Pennsylvania State University | Shrout T.R.,Pennsylvania State University
Advanced Functional Materials | Year: 2010

The electrical properties of Pb(Mg1/3Nb2/3)O 3-PbTiO3 (PMN-PT)-based polycrystalline ceramics and single crystals were investigated as a function of scale ranging from 500 μm to 30 μm. Fine-grained PMN-PT ceramics exhibited comparable dielectric and piezoelectric properties to their coarsegrained counterpart in the low frequency range (<10 MHz), but offered greater mechanical strength and improved property stability with decreasing thickness, corresponding to higher operating frequencies (>40 MHz). For PMN-PT single crystals, however, the dielectric and electromechanical properties degraded with decreasing thickness, while ternary Pb(In1/2Nb1/2)O3- Pb(Mg 1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) exhibited minimal size-dependent behavior. The origin of property degradation of PMN-PT crystals was further studied by investigating the dielectric permittivity at high temperatures, and domain observations using optical polarized light microscopy. The results demonstrated that the thickness-dependent properties of relaxor-PT ferro- electrics are closely related to the domain size with respect to the associated macroscopic scale of the samples. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA. Source

Manley M.E.,Oak Ridge National Laboratory | Lynn J.W.,National Institute of Technology NIST | Abernathy D.L.,Oak Ridge National Laboratory | Specht E.D.,Oak Ridge National Laboratory | And 4 more authors.
Nature communications | Year: 2014

Relaxor ferroelectrics exemplify a class of functional materials where interplay between disorder and phase instability results in inhomogeneous nanoregions. Although known for about 30 years, there is no definitive explanation for polar nanoregions (PNRs). Here we show that ferroelectric phonon localization drives PNRs in relaxor ferroelectric PMN-30%PT using neutron scattering. At the frequency of a preexisting resonance mode, nanoregions of standing ferroelectric phonons develop with a coherence length equal to one wavelength and the PNR size. Anderson localization of ferroelectric phonons by resonance modes explains our observations and, with nonlinear slowing, the PNRs and relaxor properties. Phonon localization at additional resonances near the zone edges explains competing antiferroelectric distortions known to occur at the zone edges. Our results indicate the size and shape of PNRs that are not dictated by complex structural details, as commonly assumed, but by phonon resonance wave vectors. This discovery could guide the design of next generation relaxor ferroelectrics. Source

TRS Technologies | Date: 2010-07-16

An antiferroelectric ceramic material that can be formed into a multilayer capacitor is disclosed. The antiferroelectric ceramic material is selected from the Pb(Sn, Zr, Ti)O3 (PSnZT) composition family.

TRS Technologies | Date: 2011-05-16

A ternary single crystal relaxor piezoelectric of PMN-PZ-PT grown from a novel melt using the Vertical Bridgeman method. The ternary single crystals are characterized by a Curie temperature, T

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