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Highlights: [•] Remarkable microstructural evolution was observed in different Sm2O3 doping levels. [•] The electrical properties can be tailored in a wide range. [•] The fracture toughness is enhanced, comparative to the dense PZT ceramics. [ABSTRACT FROM AUTHOR]

Abstract: xPb(Mg1/3Nb2/3)O3–(1−x)Pb(Zr0.47Ti0.53)O3(xPMN–(1−x)PZT) (0.15≤x≤0.30) ceramics were prepared by the conventional oxide-mixed method. The phase structure, ferroelectric and piezoelectric properties and field-induced strain behavior were systematically investigated. It was found that 0.25PMN−0.75PZT possessed superior electrical properties due to its composition close to the MPB (Morphotropic Phase Boundary). The composition near the MPB enables the existence of multiple polarization directions and consequently facilitates the domain reorientation, which should be responsible for the superior electrical properties. A large remnant polarization (P r ) of 34.2µC/cm2 and a high piezoelectric coefficient (d 33) of 698pC/N were obtained. Especially, a large field-induced strain of 2.2‰ (at 40kV/cm) was attained, which shows a great promise for actuator applications. [Copyright &y& Elsevier]

Abstract: The frequency, electric field cycling and temperature dependences of the polarization–electric field (P–E), strain–electric field (S–E) loops in poled Mn-doped 0.05Pb(Mn1/3Sb2/3)O3–0.50PbZrO3–0.45PbTiO3 ceramics have been investigated. The P–E and S–E loops are strongly asymmetric corresponding to the presence of an internal bias field E i after poling and aging, indicating that the domain walls are strongly pinned by preferentially oriented defect dipoles formed by the acceptor dopant ions (Mn2+/Mn3+) and O2− vacancies. Whereas, the loops exhibit a tendency of changing from asymmetric shapes to normal symmetric ones with increasing electric field amplitude or decreasing frequency. Repeated electric field cycling as well as high temperature results in a similar effect. Meanwhile, the E i reduces consequently, providing evidence of domain depinning or internal bias field relaxation. It is suggested that the reorientation of the defect dipoles and depinning of domain walls arising from high temperature or electric field cycling are responsible for this extrinsic internal bias field relaxation process. [Copyright &y& Elsevier]

Abstract: This investigation presents the growth of (100), (110) and preferential (111)-oriented Pb0.6Sr0.4TiO3 thin films prepared on different orientations LaNiO3 buffered silicon substrates via radio-frequency magnetron sputtering method. The effects of the orientation on microstructure and dielectric response were systematically investigated. The capacitance–voltage property versus the crystallographic orientation analysis revealed that preferential (111)-orientation film possesses the largest relative permittivity and tunability of 1180 and 84% (at 400kV/cm) respectively, which are much higher than those of (100)- and (110)-oriented thin films. These results suggest preferential (111)-orientation films as promising candidates for microwave tunable devices. [Copyright &y& Elsevier]

Temperature-dependent ferroelectric dynamic hysteresis properties of modified Pb(Mg1/3Nb2/3)O3-Pb(Zr,Ti)O3 (PMN-PZT) ceramics have been investigated in a wide range from 298 to 433 K. Interestingly, it was found that back-switching polarization Pbc increased while the hysteresis area 〈 A 〉, coercive field Ec, saturation polarization Ps, and remnant polarization Pr all decreased linearly with temperature below 398 K (close to the macro-micro domain transition temperature Tnr). A set of simple linear temperature scaling relations was established, which is different from the power-law scaling relations for soft and hard PZT ceramics. At further increased temperature, double-loop features appeared and the ferroelectric properties varied nonlinearly due to the reversible macro-micro domain transition in the T > Tnr region. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

This investigation presents a simple approach to realize the low temperature crystallization of Pb0.4Sr0.6TiO3 thin films at 400 °C by taking advantage of well controlled lead excess and kinetic-driving-force compensated thermodynamics crystalline via sputtering deposition. The thin films prepared at low temperature show fine-grained micro-structure because of the suppressed grain growth, furthermore, the intrinsic dielectric response can be modulated by the distinct level of crystallinity. The film processed at 450 °C exhibited a dielectric constant of 435 and high figure merit of 130 at 400 kV/cm, superior ferroelectric property, and stable performance with temperature and frequency. [ABSTRACT FROM AUTHOR]

Abstract: Porous Pb (Zr0.95Ti0.05) O3/xMgO (PZT/MgO, x=0, 0.1, 0.2, 0.5 and 1.0wt%) ferroelectric ceramics were prepared with MgO nanoparticles as reinforcing phase. The effects of MgO nanoparticles on the phase, microstructure, electrical and mechanical properties of as-prepared ceramics were investigated. The results show that the grain size is reduced obviously when increasing the amount of MgO. Compared with pure porous PZT, T C of MgO-added PZT ceramics shifts to higher temperature. Moreover, dielectric, ferroelectric and piezoelectric properties show no much degradation. Further, PZT/MgO ceramics possess enhanced mechanical properties compared to pure porous PZT ceramics, the largest increment of the fracture toughness and hardness being 31.3% and 19.8%, respectively. The optimal electrical and mechanical properties are obtained with the addition of less than 0.5wt% MgO nanoparticles. [Copyright &y& Elsevier]

The temperature scaling of dynamic hysteresis was investigated in Mn-doped Pb(Mn1/3Sb2/3)O3-Pb(Zr,Ti)O3 ceramic with internal bias field. A set of simple linear temperature scaling relations were established for hysteresis area , coercivity Ec, and internal bias field Ei, which are different from the power-law scaling relationships for the soft and hard PZT ceramics. The proposed scaling relation between and T can be predicted by the temperature dependent response of Ec and vice versa. It is suggested that the thermal deaging which related to the redistribution of the preferentially oriented defect dipoles is responsible for these dynamic hysteresis behaviors. [ABSTRACT FROM AUTHOR]

Polarization switching and energy storage properties of highly (100) oriented antiferroelectric (AFE) (Pb,La)(Zr,Ti)O3 thin films (≤250 nm) deposited via a sol-gel process with both LaNiO3 and Pt top electrodes were investigated. By using LaNiO3 top electrodes, the energy density as well as energy efficiency can be enhanced by 4.6 J/cm3 and 11%, respectively. Furthermore, the films with LaNiO3 top electrodes are more capable of providing high energy density over a wide temperature regime above room temperature compared to Pt. This work clearly highlights that oxide top electrodes can greatly improve the energy storage performance of antiferroelectric thin film capacitors. [ABSTRACT FROM AUTHOR]

Abstract: Pb0.4Sr0.6TiO3/LaNiO3 (PST/LNO) thin film with a perfect (100) orientation was deposited on SiO2/Si substrate by magnetron sputtering method. Both Pt and LNO top electrodes have been prepared on this film to investigate the electrical properties. The dielectric constant and piezoelectric coefficient significantly increase while the average coercive field is strongly lowered when LNO is used as the top electrode. A large tunability of 77% (@300kV/cm) and low loss factor of 2.85% were obtained. Also, a maximum and remnant piezoelectric coefficients (d 33max.eff. and d 33rem.eff.) values of 90pm/V and 47pm/V were observed. These measured properties indicate that the PST thin film is a multi-functional material, which is a promising candidate for piezoelectric applications and for tunability devices. [Copyright &y& Elsevier]

The evolution of dynamic hysteresis of lead zirconate titanate stannate antiferroelectric bulk ceramics at various frequencies ( f) and field amplitudes ( E0) has been investigated systematically. A series of asymmetrical minor loops were observed when the working fields were slightly lower than the forward switching field EAF. As E0 increased above EAF, symmetrical double loops appeared and their energy densities w against f and E0 were found to be fit the scaling behavior as w [ABSTRACT FROM AUTHOR]

The doped 0.25 Pb(Mg1/3 Nb2/3) O3-0.40 PbTiO3-0.35 PbZrO3 ( PMN-PZT) ceramics with pure perovskite phase were prepared by one-step oxide-mixed method and conventional columbite method. The phase structure and electrical properties were systematically investigated. Crystallites of the ceramic fabricated by the oxide-mixed method are partially oriented with the c-axis, while samples prepared from columbite method are randomly oriented. This crystalline orientation enabled better electric properties, especially a higher piezoelectric coefficient d33 of 760 pC/N and electromechanical coupling factor kp of 69%. Materials fabricated from the oxide-mixed method are attractive for high-performance piezoelectric actuator and this simple method may have a great prospect in industrial production. [ABSTRACT FROM AUTHOR]

Lead zirconate titanate ceramics with different contents of excess PbO, Zr/Ti ratios, and carbon nanotubes ( CNTs) addition were fabricated by conventional solid-state reaction sintering in air. The effect of PbO content, Zr/Ti ratio, and the addition of CNTs on the formation of intragranular pores in Pb(Zr0.95Ti0.05)O3 ferroelectric ceramics were studied by scanning electron microscopy measurements. It was found that the formation mechanism of porous-grained ceramics is tightly associated with the stoichiometry of PbO and the addition of CNTs. The physical mechanism of the intragranular pore formation, that the insufficiency of PbO and the introduction of the CNTs decrease the densification process by inhibiting mass transportation during sintering stage, was tentatively proposed based on the sintering theory. The ferroelectric properties of the ceramics were characterized and correlated with their microstructures. [ABSTRACT FROM AUTHOR]

Energy-storage properties of 0.89 Bi0.5Na0.5TiO3-0.06 BaTiO3-0.05 K0.5Na0.5NbO3 (0.89 BNT-0.06 BT-0.05 KNN) lead-free ceramics were first investigated. Measurements of dielectric properties together with switching current curves indicate a rather diffuse ferroelectric ( FE) to anti-ferroelectric ( AFE) phase transition when heating from 20°C to 90°C. The energy density ( W), which was calculated from P-E hysteresis loops, increases linearly with the external electric field when E exceeds AFE- FE transition field. W is independent of temperature and frequency, and maintains around 0.59 J/cm3 under 5.6 kV/mm in the stable AFE phase region. These properties indicate that 0.89 BNT-0.06 BT-0.05 KNN ceramics might be a promising lead-free AFE material for energy-storage capacitor application. [ABSTRACT FROM AUTHOR]

PbxSr1-xTiO3 ( PST) thin films with the ratio Pb/Sr = 40/60 were deposited on silicon substrate with Pt or LaNiO3 ( LNO) bottom electrodes by radio frequency magnetron sputtering followed by a postannealing treatment. The structural and microstructural analyses were performed and a perovskite phase was obtained whatever the nature of the bottom electrodes and even at a low temperature (450°C). The optimal annealing temperature is 650°C at which the films have a dense and fine microstructure. For electrical characterization the different top electrodes ( Pt and LNO) were used. In both cases, we demonstrate that PST films present excellent performances in terms of dielectric properties and in particular, the tunability and Figure of Merit. A large tunability (57% at 400 kV/cm) and low dielectric losses (1.4%) were measured at 10 kHz for Pt/PST/Pt structures postannealed at 500°C. For LNO/PST/LNO structures, postannealed at 650°C, the improved tunability (≈80%) and low loss factor (≈2%) were obtained. Prospects of PST as an alternative to BST for tunable applications with a real potentiality of monolithic integration with silicon, in terms of thermal budget, are considered. [ABSTRACT FROM AUTHOR]

Frequency ( f) dependence of coercive field ( Ec) of six Pb( Zr1− x Ti x) O3 (0.20 ≤ x ≤ 0.60) bulk ceramics with different compositions was investigated at various frequencies (1-100 Hz). Scaling relations of Ec against f, Ec ∝ f β, were obtained, where the value of exponent β varied with the ceramics composition. These exponents were far smaller than that of the theoretic prediction because the domain wall motion played a major role in the frequency region. In addition, the values of the exponents were of obvious discrepancy for different phase structures with tetragonal, rhombohedral, and morphotropic phases, but nearly similar for the same phase structure with different compositions, suggesting that different domain structures influence the scaling behaviors. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline La0.7Sr0.3MnO3 (LSMO) films were prepared on SiO2/Si (001) substrates by chemical solution deposition technique. Electrical and magnetic properties of LSMO were investigated. A minimum phenomenon in resistivity is found at the low temperature () under magnetic fields from 0 T to 3 T. Kondo-like spin dependent scattering, which includes both spin polarization and grain boundary tunneling, was observed in the low-temperature electrical transport for the LSMO polycrystalline films. The temperature-dependent resistivity at low temperatures can be well fitted in the framework of elastic scattering, electron–electron (e–e) interaction, Kondo-like spin dependent scattering, and electron–phonon (e–ph) interaction. [Copyright &y& Elsevier]

Abstract: Porous Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 ferroelectric ceramics with different pore size were prepared by solid-state sintering in air. The microstructural effect on the properties has been systematically investigated by SEM, ferroelectric hysteresis, strain–electric field curves and breakdown strength measurements. The results demonstrate that the microgeometry has a subtle effect on the ferroelectric and dielectric properties. However, the results also demonstrate that the electric field induced strain and the dielectric breakdown strength decreases with the increase of pore size. [Copyright &y& Elsevier]

Abstract: Poled Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 ferroelectric ceramics in different porosity depoled under shock wave load. Porosity and material dielectric characteristic effects on the depoling current evolution were discussed. The results showed that under open circuit condition, the dielectric constant of all samples exhibited obvious increase, but as the porosity increased, the dielectric constant decreased. As a result of lower dielectric constant of porous samples during depoling process, the charge-releasing rate is faster than that of dense sample. [ABSTRACT FROM AUTHOR]

The hysteresis behaviors and phase characteristics of Pb0.97La0.02(Zr0.90Sn0.025Ti0.075)O3 ( PLZST) ceramics were investigated in this work. A single mini hysteresis loop at 3 kV/mm with the maximum polarization ( Pmax) of 8.3 μC/cm2 and triple hysteresis loops at 6.6 kV/mm were observed, which indicates the coexistence of rhombohedral ferroelectric phase and tetragonal antiferroelectric phase. The X-ray Diffraction patterns and dielectric temperature spectra both demonstrate this coexistence. Moreover, the hysteresis loops with increasing temperature indicated that a ferroelectric-antiferroelectric phase transition occurred at about 60°C. These phenomena would be useful for understanding the domain evolution during ferroelectric and antiferroelectric phase transition. [ABSTRACT FROM AUTHOR]

PbZr0.35Ti0.65O3 (PZT), PbZrO3 (PZO), and PZT/PZO ferroelectric/antiferroelectric multilayer films were prepared on a Pt/Ti/SiO2/Si substrate using the sol–gel method. Microstructures and physical properties such as the polarization behaviors, leakage current, dielectric features, and energy-storage characteristics of the three films were systematically explored. All electric field-dependent phase transitions, from sharp to diffused, can be tuned by layer structure, indicated by the polarization, shift current, and dielectric properties. The leakage current behaviors suggested that the layer structure could modulate the current mechanism, including space-charge-limited bulk conduction for single layer films and Schottky emission for multilayer thin films. The electric breakdown strength of a PZT/PZO multilayer structure can be further enhanced to 1760 kV/cm, which is higher than PZT (1162 kV/cm) and PZO (1373 kV/cm) films. A recoverable energy-storage density of 21.1 J/cm3 was received in PZT/PZO multilayers due to its high electric breakdown strength. Our results demonstrate that a multilayer structure is an effective method for enhancing energy-storage capacitors. [ABSTRACT FROM AUTHOR]

Abstract: A modified citrate precursor method, combining the advantages of the nitrate autocombustion method by introducing the nitric acid, was successfully used to synthesize ultrafine Ba0.70Sr0.30TiO3 powders. Slight agglomerated and homogenized BST powders, with an average particle size of 20nm, were obtained at 800°C. Combining the results of TG/DTA and XRD, it can be concluded that the formation of BST powders takes place via two reaction mechanisms: decomposition of an intermediate oxycarbonate mechanism (DIOm) at low temperature, and solid-state reaction mechanism (SSRm) between nanocrystalline carbonates and amorphous TiO2 at high temperature. TEM shows higher amount of CA led to BST powders of better quality in morphology. Based on results of chemical analysis, it is suggested that higher amount of CA drives the mechanism to tend to DIOm. By simply adjusting the ratio of reagents, the reaction mechanism can be dominated and we can greatly control the final morphology of the powders. [Copyright &y& Elsevier]

Abstract: Ferroelectricity in Langmuir–Blodgett (LB) films (Z-type and alternated Y-type) of nitrogencrown (NC) and arachidic acid (AA) was investigated by electric polarization measurements and small angle X-ray diffraction (SAXD). For Z-type AA LB multilayer and the AA LB films incorporating barium ions, as well as for Z-type NC LB multilayer and the Y-type NC/AA alternating LB films, hysteresis loops of the samples were observed and confirmed existence of the remnant polarizations in the LB films. Their corresponding remnant polarizations were found to be 15, 180, 450 and 9400μCm−2, respectively. Therefore, the maximum ratios of remnant polarizations up to 620 (9400/15)-folds were obtained from NC/AA alternating LB films. The enhancement of ferroelectricity in NC/AA alternating LB films was observed for the first time. It was demonstrated that the enhancement of ferroelectricity in the LB films could be created by incorporation of barium ions into the LB film structures and strong interaction due to electron clouds redistribution largely originated from the compact insertion configuration of AA between two chains of NC molecules in interleaving films. [Copyright &y& Elsevier]

Abstract: Pyroelectric properties in alternating hemicyanine (DAEP)/nitrogencrown (NC) Langmuir–Blodgett (LB) films and effects of incorporating barium cations on pyroelectric behaviors have been investigated. Its pyroelectric coefficient measured is found to be 58μCm−2 K−1at 300K. Their dielectric properties have been measured and used to determine the figures of merit in thermal devices. Relative permittivity (ɛ r) and dielectric loss values (tan δ) of pyroelectric films (in the range of 1–100KHz) are found to be 2.34–1.96 and 0.08–0.04, respectively. These data give a maximum pyroelectric figure of merit of 150μCm−2 K−1 in the alternating LB films incorporating barium ions. The effects of different deposition on pyroelectric properties are also discussed in this paper. [Copyright &y& Elsevier]

Investigates ferroelectricity in Langmuir-Blodgett (LB) films of nitrogencrown and arachidic acid by electric polarization measurements and surface pressure-molecular area isotherm. Hysteresis loops; Existence of remnant polarizations in the LB films; Enhancement of ferroelectricity.

The optical properties of amorphous PbZr0.52Ti0.48O3 thin films on vitreous silica and sapphire substrates by the RF magnetron sputtering method have been investigated by transmittance measurements. For a single-layer thin film on the transparent substrate, the inverse synthesis or fitting method with the six fitting parameters was given and used to calculate the optical constants such as the refractive index n, the extinction coefficient k, and the absorption coefficient α. The film thickness d, which was one of the fitting parameters, is simultaneously obtained. According to Tauc''s law, the optical transition in amorphous PbZr0.52Ti0.48O3 thin films is direct in nature. The direct band gaps of amorphous PbZr0.52Ti0.48O3 thin films on vitreous silica and sapphire substrates were found to be 3.36 and 3.25 eV, respectively. The dispersions of the refractive index in films were studied by considering a single-oscillator model. [Copyright &y& Elsevier]

Abstract: This investigation presents a novel method to prepare Pb0.4Sr0.6TiO3 thin films crystallized at relatively low temperature with different microstructures and enhanced tunability performance on LaNiO3 buffered SiO2/Si substrates. The incorporation of oxygen during the ex-situ RF magnetron sputtering unusually changes the microstructure of the films and remarkably improves the tunability because of the modulated dielectric constant with and without electric field. The dielectric response versus the DC electric field analysis revealed that the tunablity increased from 61.6% to 73.4% at ±400kV/cm with increasing content of oxygen while the loss factor retained relatively low, suggesting the film could be one of the promising candidates for the microwave tunable devices compatible with Si integrated circuits. [Copyright &y& Elsevier]

Pyroelectric response mechanism of Ba0.70Sr0.30TiO3 ceramics under dielectric bolometer (DB) mode was investigated by dielectric and pyroelectric properties measurement. The variations of total, intrinsic, and induced pyroelectric coefficients (ptot, pint, pind) with temperatures and bias fields were analyzed. pint plays the dominant role to ptot through most of the temperature range and pind will be slightly higher than pint above T0. The essence of the enhancing effect of DC bias field on pyroelectric coefficient can be attributed to the high value of pint. This mechanism is useful for the pyroelectric materials (DB mode) applications. [ABSTRACT FROM AUTHOR]

Highly (100) oriented lead strontium titanate ( Pb0.4 Sr0.6 TiO3) thin films were deposited on LaNiO3 -coated Si substrate via radio-frequency magnetron sputtering method with substrate temperature ranging from 300 to 500°C. The PST thin films were crystallized at a temperature as low as 300°C, which may result from the well-controlled stoichiometry and the in situ crystallization on seed layer. At an electric field of 400 kV/cm, high tunability of 43% and 57% can be achieved for PST films deposited at 300°C and 500°C, respectively. Moreover, the dielectric response shows weak frequency dependence and the loss factor stays relatively low. The results suggest that such films should be promising candidate for the microwave tunable devices compatible with the current Si technology. [ABSTRACT FROM AUTHOR]

Antiferroelectric Pb(Zr, Nb, Ti)O3 (PZNT) films were deposited via a sol-gel process on Pt(111)/Ti/SiO2/Si, LaNiO3- and La0.5Sr0.5CoO3-buffered Si substrate. The scaling behavior of the energy density W of antiferroelectric films was investigated. The scaling behavior of W against frequency f of PZNT on LaNiO3-buffered Si takes the form of W ∝ f0.08, which differs significantly from that form of W ∝ f-0.14 of PZNT on La0.5Sr0.5CoO3-buffered Si. This indicates that the scaling relations of W vary substantially as bottom electrodes change and might be closely related to the variation of nonuniform strain field and depolarization field within the AFE films. [ABSTRACT FROM AUTHOR]

Abstract: A phase diagram for the lead-free ceramics in the (1−x%)(0.89Bi0.5Na0.5TiO3–0.06BaTiO3–0.05K0.5Na0.5NbO3)–x%MnO2 (BNBKN-x%Mn) binary system is constructed for the first time based on the ferroelectric and dielectric measurements. The ferroelectric behaviors under different temperatures suggest that the ceramics are basically of relaxor anti-ferroelectric nature near room temperature. The temperature dependent dielectric properties show that when the addition of MnO2 increases, the relaxor anti-ferroelectric phase can be stabilized to be close to the Curie point, which corresponds to a relaxor anti-ferroelectric to paraelectric phase transition. [Copyright &y& Elsevier]

The (0.9−x) Bi0.5Na0.5TiO3-xBaTiO3-0.1K0.5Na0.5NbO3 [ BNBKN(x), x = 0.060, 0.063, 0.066, and 0.069] ceramics were fabricated by the conventional sintering technique. The P- E hysteresis loops measured under 5 kV/mm at room temperature show that the BNBKN(0.063) ceramics obtain the maximum ( Ps− Pr) value of 20.6 μC/cm2 and the largest energy-storage density W of 0.424 J/cm3. In addition, calculation from the X-ray diffraction results shows that the BNBKN(0.063) ceramics are featured with the largest c/ a ratio of 0.70887. The W is observed to increase with the increase of the c/ a ratio in the BNBKN( x) ceramics. The c/ a ratio can be regarded as a significant factor for W in the BNBKN( x) ceramics. [ABSTRACT FROM AUTHOR]

Abstract: The magnetodielectric properties of BSPT/LSMO multiferroic composite thin films were investigated through the measurement of the frequency dependence of the dielectric constant under different magnetic fields at room temperature. The magnetodielectric (MD) response showed strong frequency dependence: at 100 Hz, the MD response remained negative and the maximum value of −1.1% was obtained; at 52 kHz, the dielectric constant first decreased and then rose linearly with the magnetic field until the giant room temperature positive MD effect of 9.5% was derived under 7 T. The observed unique MD effects for BSPT/LSMO were attributed to the co-contributions of the magnetostriction and magnetoresistance. [Copyright &y& Elsevier]

Abstract: Polarization–field (P–E) hysteresis loops of – bulk ceramics were measured under sinusoidal electric fields over a frequency range of Hz and an amplitude range of 20–50 kV/cm. The scaling relations of the hysteresis loop area versus the frequency and amplitude of the applied field for the saturated loops take different forms in the low and high frequency ranges. From these two relations, it can be concluded that the relationship is a power law increase in the low frequency range while in the high frequency range the relationship turns into a power law decrease. [Copyright &y& Elsevier]

• E-field controlled magnetism in an AFE-based YIG/PLZST heterostructure shows potentials for creating device functionalities. • A large CME coefficient (11.6 × 10−8 s/m) is obtained at 0 Oe. • E-field tuning of susceptibility variation can reach 33% at a low magnetic field of 10 Oe. The magnetoelectric properties of a laminated heterostructure consisting of ferromagnetic yttrium iron garnet (YIG) film and antiferroelectric (Pb 0.97 La 0.02) (Zr 0.6 Sn 0.3 Ti 0.1)O 3 (PLZST) ceramic is, for the first time, reported in this work. The electric-field-controlled susceptibility, a shift of the coercive magnetic field and magnetization variations are demonstrated in YIG/PLZST multiferroic heterostructure. A large variation of the relative magnetic susceptibility is observed, practically 33% at a low magnetic field of 10 Oe. A sharp reduction of magnetization occurs at the antiferroelectric-ferroelectic phase transition field of PLZST ceramic. Thus the converse magnetoelectric coefficient peaks at the switching field and the maximum can reach 11.6 × 10−8 s/m without bias magnetic field. These features indicate that antiferroelectric materials can also be alternative candidates to combine with ferromagnetic materials for magnetoelectric tunable devices. [ABSTRACT FROM AUTHOR]

• Obtained the PLZST ceramics with "slanted" shape of P-E loops by modifying Sn content. • Obtained a high recoverable energy density of 1.42 J/cm3 and high η of 90% in PLZST30/60/10. • Better understanding of the mechanism on energy storage properties of PLZST ceramics. Both high energy density and high energy efficiency are indispensable as considering antiferroelectric materials for pulse power capacitor applications. However, the electrical hysteresis will inevitably limit the energy efficiency reported in previous literatures. In this work, lead lanthanum zirconate stannate titanate (PLZST) antiferroelectrics with both high energy density and high energy efficiency was presented. It is found that PLZST antiferroelectric ceramics with high Sn content not only exhibit enhanced antiferroelectricity, but also demonstrate higher energy efficiency. As Sn content increases, grain size decreases and the electric hysteresis values reduces. The high energy density of 1.28 J/cm3 and ultrahigh energy efficiency of 91% was obtained for PLZST30/60/10. The results will not only enrich our understanding of PLZST antiferroelectric materials but also offers new approach to developing high performance antiferroelectric for energy storage based applications. [ABSTRACT FROM AUTHOR]

A correction to the article "Magnetic field modulated dielectric relaxation behavior of Pt/BiScO3-PbTiO3/La0.7Sr0.3MnO3 heterostructure in metal-insulator transition region: An equivalent-circuit method" that was published online on January 19, 2012 is presented.

Both high pyroelectric properties and good temperature stability of ferroelectric materials are desirable when used for applications in infrared thermal detectors. In this work, we report lead-free ternary 0.97(0.99Bi0.5Na0.5TiO3-0.01BiAlO3)-0.03K0.5Na0.5NbO3 (BNT-BA-KNN) ceramics, which not only exhibits a large pyroelectric coefficient (p ∼ 3.7 × 10−8 C cm−2 K−1) and figures of merit (Fi, Fv, and Fd) but also shows excellent thermal stable properties. At room temperature, Fi, Fv, and Fd are determined as high as 1.32 × 10−10 m/V, 2.89 × 10−2 m2/C, and 1.15 × 10−5 Pa−1/2 at 1 kHz and 1.32 × 10−10 m/V, 2.70 × 10−2 m2/C, and 1.09 × 10−5 Pa−1/2 at 20 Hz, respectively. During the temperature range of RT to 85 °C, the achieved p, Fi, Fv, and Fd do not vary too much. The high depolarization temperature and the undispersed ferroelectric-ergodic relaxor phase transition with a sharp pyroelectric coefficient peak value of ∼400 × 10−8 C cm−2 K−1 are suggested to be responsible for this thermal stability, which ensures reliable actual operation. The results reveal the BNT-BA-KNN ceramics as promising lead-free candidates for infrared thermal detector applications. [ABSTRACT FROM AUTHOR]

Several 0.97PbZrO3–0.03Ba(Mg1/3Nb2/3)O3 (0.97PZ–0.03BMN) ceramics were prepared via the columbite precursor method. Their microstructures and pressure-dependent ferroelectric and depolarization performances were then studied. The X-ray diffraction patterns of ground and fresh samples indicate that a main rhombohedral symmetry crystal structure is present in the bulk and that it sits alongside a trace quantity of an orthorhombic antiferroelectric phase that results from the effect of grinding on the surface. The remanent polarization (Pr) of the 0.97PZ–0.03BMN reached 32.4 μC/cm2 at 4.5 kV/mm and ambient pressure. In an in situ pressure-induced current measurement, more than 91% of the retained Pr of the pre-poled sample was released when the pressure was increased from 194 MPa to 238 MPa. That this pressure-driven depolarization should be attributed to the pressure-induced ferroelectric–antiferroelectric phase transition is supported by the emergence of double P–E loops at high hydrostatic pressures. Moreover, the 0.97PZ-0.03BMN ceramics exhibit no temperature-induced phase transitions and little related polarization loss up to 125 °C, which suggests that Pr has excellent thermal stability. The sharp depolarization behavior at low pressures and excellent temperature stability reveal that our 0.97PZ–0.03BMN ceramics exhibit superior performances in mechanical–electrical energy conversion applications. [ABSTRACT FROM AUTHOR]

The correlation between films thickness and the physical properties (such as magnetic, magnetotransport properties) has been investigated in 5 nm and 160 nm La 0.7 Sr 0.3 MnO 3 (LSMO). The films were deposited on (100) SrTiO 3 (STO) substrates by chemical solution deposition method. High-resolution X-ray diffraction (HRXRD) and high-resolution transmission electron microscopy have been used to estimate the epitaxial structure and the change of strain. Both of the films are grown on STO substrates with coherent interfaces. The thinner sample has fully strained while the thicker film is partially strain relaxation. With decreasing film thickness from 160 to 5 nm, both of the T C and T MI strongly depressed. The strain and limitation of the spin fluctuations by the film thickness are the main origins of the Tc lowering. The MR value of S1 is much larger than that of S2 at 300 K. It can be elucidated by the existence of magnetic polarons around T C and spin fluctuations in the interface between the film and the substrate. [ABSTRACT FROM AUTHOR]

La 0.7 Ca 0.3 MnO 3 (LCMO)/La 0.7 Sr 0.3 MnO 3 (LSMO) multilayer films have been successfully prepared on (100) oriented SrTiO 3 substrates by chemical solution deposition method. The relationship between the multilayer structure and physical properties was systematically studied. X-ray diffraction (HRXRD) patterns of θ−2θ scan show that both of the films have perfect crystalline orientation. Reciprocal space maps (RSM) of the multilayer films show that the multilayer films are epitaxial growth and fully strained. Independent ferromagnetic - paramagnetic transition of LCMO and LSMO layer are visible as a function of the temperature, which indicates that the magnetization of the individual layers can rotate independently of each other. The maximum value of absolute MR is increased slightly as the layer number increasing. It can be attributed to the spin-polarized tunneling which is associated with magnetic domain rotation at the interface. [ABSTRACT FROM AUTHOR]

La 0.7 Ca 0.3− x Sr x MnO 3 ( x =0, 0.10, 0.15, 0.25 and 0.30) thin films were prepared by the sol–gel method on Si substrates. The structural, magnetic and transport properties were systematically studied. All the LCSMO thin films crystallized perfectly with a random crystalline orientation. The films show strong coupling between lattice and physical properties. With the increment in x , the lattice parameter increases, the magnetic properties are enhanced, and the T c increases monotonically from 235 K to 343 K. Resistivity is dramatically decreased with Sr dopant. The temperature corresponding to the MR maxmium value is close to that of the T MI for LCMO, while there was no peak value for Sr doped thin films in this temperature range. [ABSTRACT FROM AUTHOR]

(1− x )(Ba,Sr)TiO 3 – x ZnAl 2 O 4 ( x =0.00, 0.05, 0.10 and 0.20) composites were prepared by the traditional solid state reaction. The dielectric, tunable and Raman spectroscopy properties are studied. The curie temperature of the composites does not show much difference due to low solubility between BST and ZnAl 2 O 4 . For the composition with x =0.20, its tunability is up to 46.4% (@2 kV/mm), nearly 1.5 times of that of pure BST, and meanwhile its dielectric constant and loss are decreased. The results imply that making non- or little-soluble BST-nonferroelectric composites is a very effective way to keep high tunability and low dielectric constant simultaneously. Raman results confirm that there are some residual polar microregions in (1− x )BST– x ZnAl 2 O 4 composite, and their extrinsic contribution to the dielectric tunability is responsible for a deviation from the ε versus E behavior predicted by Johnson׳s equation. [ABSTRACT FROM AUTHOR]

The effect of residual stress on energy storage property was investigated for a series of PbZrO3 thin films on SrTiO3 and Si substrates. Compressive or tensile residual stress influences the critical electric field EA for the ferroelectric-to-antiferroelectric phase transition, thus for films with (110)/(101) orientation, energy density W of films on SrTiO3 is 38% larger than films on Si; in contrast, (001)-oriented PbZrO3 films on SrTiO3 show slightly smaller W compared to films on Si. We conclude that the different responses of W to stress are related to the different constrain states in films with different orientations. [ABSTRACT FROM AUTHOR]

Large strain memory effect was confirmed in the poled and aged Mn-doped 0.05Pb(Mn1/3Sb2/3)O3-0.50PbZrO3-0.45PbTiO3 ceramics due to the presence of asymmetric strain hysteresis curve with two stable strain states at zero electric field. This strain memory is two times larger than that of the unipolar strain output. Moreover, the large strain memory effect is quite stable at high electric field or down to 0.01 Hz and shows good stability even after 20 000 fatigue cycles. These results indicate that strain memory piezoelectric actuator, which could keep its output strain without any operating fields, may be fabricated using this kind of material. [ABSTRACT FROM AUTHOR]

Cax(Sr0.5Ba0.5)1-xNb2O6 [CSBN(x), x = 0.00, 0.10, 0.15, and 0.20] lead-Free ceramics were prepared by a traditional solid-state reaction technique. Dielectric, ferroelectric, and pyroelectric properties of CSBN(x) lead-Free ceramics were systematically investigated. The pyroelectric properties of CSBN(x) have been enhanced remarkably due to Ca addition and reached the maximum values at x = 0.15, with pyroelectric coefficient of 3.61 × 10-8 C/cm2 K and pyroelectric figure of merit of Fi = 172 pm/V, Fv = 0.021 m2/C, and Fd = 11.5 μPa-1/2, which are superior to other lead-free ferroelectric ceramics. These results indicate the potential of CSBN(x) ceramics for infrared detector applications. [ABSTRACT FROM AUTHOR]

(Pb0.325Sr0.675)TiO3 (PST) ceramics were prepared by a traditional solid-state reaction technique. The dielectric and enhanced pyroelectric properties of PST ceramics were investigated under a DC bias field. The dielectric permittivity and dielectric loss of PST ceramics at Curie temperature were 2.97 × 10-4 and 0.006 without DC bias field, respectively. With a DC electric field of 0-500 V/mm, the maximum pyroelectric coefficient and the largest figure of merit (Fd) of PST ceramics were obtained, about 60 × 10-8 C cm-2 K-1 and 26 × 10-5 Pa-1/2, respectively. PST ceramics with such superior electric field enhanced pyroelectric properties have the potential for uncooled focal plane array detectors application. [ABSTRACT FROM AUTHOR]