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As a typical lead-free antiferroelectric material, silver niobate has attracted much attention in recent years due to its excellent performance in energy storage. In this work, based on a spherical aberration–corrected STEM-high angle annular dark field technique, the sites of each cation column of pure silver niobate and Ta-doped silver niobate were quantitatively obtained. Besides conventional antiferroelectric displacements along the ±[1−10]c directions, B-site ions were found to also deviate along ±[001]c directions and form many local off-centering nanoregions, which may induce weak ferroelectricity, just like polar nanoregions in relaxed ferroelectrics. Such results will further increase our understanding of silver niobate in the microscopic view and may help explain some unsolved questions. [ABSTRACT FROM AUTHOR]

The development of electronic materials for storing electrical energy is a thriving research field, where the materials used in batteries, supercapacitors, and dielectric capacitors have attracted extensive interest in last decades. The dielectric capacitors showing unique characteristics such as high power density and large charge/discharge rate have been actively studied, where the antiferroelectrics demonstrate great potentials for dielectric energy storage applications by storing and releasing energy upon a reversible electric-field induced antiferroelectric- ferroelectric phase transition. Recently, lead-free antiferroelectric AgNbO3 has emerged as a promising candidate to substitute conventional lead-based antiferroelectrics (such as PbZrO3) in energy storage applications. The phase transition dynamics of AgNbO3 is driven by a complex sequence of oxygen octahedron tilting orders in addition to cation displacement, which can be effectively engineered by a doping strategy. In this article, we present a succinct overview of the phase transition mechanisms in AgNbO3-based ceramics and describe how the phase transition characteristics are affected by the dopants. By exploring the composition related average structure and local structural evolutions, we provide a view toward the goal of establishing a link between the phase transition and physical properties tailored for dielectric energy storage applications. The development of electronic materials for storing electrical energy is a thriving research field, where the materials used in batteries, supercapacitors, and dielectric capacitors have attracted extensive interest in last decades. The dielectric capacitors showing unique characteristics such as high power density and large charge/discharge rate have been actively studied, where the antiferroelectrics demonstrate great potentials for dielectric energy storage applications by storing and releasing energy upon a reversible electric-field induced antiferroelectric- ferroelectric phase transition. Recently, lead-free antiferroelectric AgNbO3 has emerged as a promising candidate to substitute conventional lead-based antiferroelectrics (such as PbZrO3) in energy storage applications. The phase transition dynamics of AgNbO3 is driven by a complex sequence of oxygen octahedron tilting orders in addition to cation displacement, which can be effectively engineered by a doping strategy. In this article, we present a succinct overview of the phase transition mechanisms in AgNbO3-based ceramics and describe how the phase transition characteristics are affected by the dopants. By exploring the composition related average structure and local structural evolutions, we provide a view toward the goal of establishing a link between the phase transition and physical properties tailored for dielectric energy storage applications. [ABSTRACT FROM AUTHOR]

Rare-earth element-doped BiFeO3 has an ultrahigh piezoelectric response near the morphotropic phase boundary (MPB), making it a promising substitute for toxic lead-based piezoelectric materials. As a ferroelectric–antiferroelectric MPB, its microscopic mechanism, especially the contribution of each phase to the piezoelectric performance, is still unclear. In this work, the origin of the giant piezoelectric response of Sm-doped BiFeO3 thin films was studied by combining nanoscale in situ electric field experiments and atomic-resolution electron microscopy. Two independent reversible phase transitions were found under an external electric field: a phase transition between the polar and nonpolar phases and a phase transition between the polar and antipolar phases. Calculations indicated that the enhancement of the piezoelectric response at the MPB originated from these two reversible phase transitions, which were realized via the nucleation of the nanoscale new phase and the motion of the phase boundary under the external electric field. The above results provide deeper insight into the mechanism of the electromechanical response near the ferroelectric–antiferroelectric MPB in rare-earth element-doped BiFeO3 thin films. [ABSTRACT FROM AUTHOR]

The leakage current of BiFeO3 thin films can be reduced by Sm or Ti doping, and their codoping effect is significant. X-ray photoelectron spectroscopy revealed that the reduction in the leakage current can be ascribed to decreased Fe2+ ions and oxygen vacancies. The leakage mechanisms of pristine and doped BiFeO3 films were studied by analyzing their leakage current characteristics through curve fitting. It was found that Ti could stabilize the trapped carriers, while Sm might decrease the trap energy and contrarily benefit the excitation of the trapped carriers, which explains the greater effect of Ti in reducing the leakage current than that of Sm. The piezoelectric properties of Sm/Ti-codoped BiFe0.9Ti0.1O3 (BFO) films were comparable to those of pristine BFO owing to the enhanced electric breakdown despite their reduced remanent polarization. [ABSTRACT FROM AUTHOR]

We describe the design, fabrication, and testing of a spectroscopic refractometer that employs plasmonic interferometry to measure the optical dielectric functions of materials in the visible range. The proposed device, dubbed a plasmonic refractometer, consists of an array of slit-groove plasmonic interferometers etched in a ~300 nm-thick metal film (silver or gold) with arm lengths varying in steps of 25 nm up to ~8 lm. The nano-groove in each interferometer is able to generate propagating surface plasmon polaritons efficiently in a broad wavelength range, without requiring prism- or grating-coupling configurations. An integrated microfluidic channel ensures uniform delivery of dielectric materials in liquid phase. Spectrally resolved plasmonic interferograms are generated by measuring light transmission spectra through the slit of each slit-groove plasmonic interferometer and plotting the normalized intensity as a function of arm length (0.26-8.16 μm) and incident wavelength (400-800 nm) for various combinations of metal/dielectric materials. Fits of the plasmonic interferograms with a surface plasmon interference model allow determination of the refractive index dispersion of a broad class of dielectric materials, over a wide range of wavelengths and dielectric constants. As proof of concept, we extract and report the dielectric functions of representative materials, such as silver, gold, water, methanol, and ethanol. [ABSTRACT FROM AUTHOR]

Robust resistivity against electrical cycling at not only ambient conditions but also enhanced temperatures is an essential requirement for high-end actuator applications. In this study, the temperature and electric field dependence of unipolar fatigue behaviors of CaZrO3-modfied (K, Na)NbO3 lead-free piezoceramics were investigated. The space charge accumulation during unipolar cycling is responsible for the build-up of internal bias field, the dynamics of which with respect to temperature and driving field can be described using a model based on Maxwell-Wagner relaxation process. Besides, clamping of domain walls can be inferred by comparing the large and small signal permittivity. Most intriguingly, the unipolar strain exhibits a fatigue-free behavior even at elevated temperatures, rendering the material exceptionally suitable for actuator applications. [ABSTRACT FROM AUTHOR]

The mechanical properties, electronic structure and thermodynamic properties of the Mo2XB2 and MoX2B4 (X=Fe, Co, Ni) ternary borides were calculated by first-principles methods. The elastic constants show that these ternary borides are mechanically stable. Formation enthalpy of Mo2XB2 and MoX2B4 (X=Fe, Co, Ni) ternary borides are at the range of -118.09 kJ/mol to -40.14 kJ/mol. The electronic structures and chemical bonding characteristics are analyzed by the density of states. Mo2FeB2 has the largest shear and Young's modulus because of its strong chemical bonding, and the values are 204.3 GPa and 500.3GPa, respectively. MoCo2B4 shows the lowest degree of anisotropy due to the lack of strong direction in the bonding. The Debye temperature of MoFe2B4 is the largest among the six phases, which means that MoFe2B4 possesses the best thermal conductivity. Enthalpy shows an approximately linear function of the temperature above 300K. The entropy of these compounds increase rapidly when the temperature is below 450 K. The Gibbs free energy decreases with the increase in temperature. MoCo2B4 has the lowest Gibbs free energy, which indicates the strongest formation ability in Mo2XB2 and MoX2B4 (X=Fe, Co, Ni) ternary borides. [ABSTRACT FROM AUTHOR]

Electrical poling is indispensable for endowing isotropic ferroelectric polycrystals with a net macroscopic polarization and hence piezoelectricity. However, little attention has been paid to the optimization of poling conditions in (K, Na)NbO3-based ceramics with a polymorphic phase transition. This study investigated the electrical properties of CaZrO3-modified (K, Na, Li)(Nb, Ta)O3 lead-free piezoceramics as a function of the poling temperature. Peak piezoelectric coefficient d33 of 352 ± 7 pC/N and planar electromechanical coupling factor kp of 0.47 were obtained at the optimized poling temperature of 120 °C, which crosses the polymorphic phase transition regime. In-depth analysis of the asymmetric polarization hysteresis loops and bipolar strain curves uncovered striking analogy between electrical poling and unipolar cycling in the current system, which is attributed to a competition between domain reorientation and space charge accumulation. [ABSTRACT FROM AUTHOR]

We report on temperature dependence of local electromechanical properties of lead-free (K,Na)NbO3-based ceramics that macroscopically manifests a large temperature-insensitive strain. Piezoresponse force microscopy reveals the particular role of the orthorhombic-tetragonal phase transition, where a reconstruction of the domain structure occurs and local piezoelectric response shows a peak value. A good quantitative agreement between temperature dependences of the local and previously reported macroscopic small-signal piezoelectric coefficients is observed. An influence of the polymorphic phase transition on polarization switching kinetics was revealed. [ABSTRACT FROM AUTHOR]

We present a theoretical analysis of liquid viscosity sensors using ZnO and AlN thin film bulk acoustic wave resonators (FBARs) with tilted polar c-axis orientations. Besides the thickness longitudinal mode, the tilted c-axis orientation induces thickness shear mode in the resonator, which allows resonators operated in liquid medium without significant damping for sensory application. The equation for predicting electric impedance of shear mode film bulk acoustic wave resonators (FBARs) with a viscous liquid loading was derived from the basic piezoelectric constitutive equations. The viscosity sensitivity of shear mode ZnO and AlN resonators was achieved by calculation of resonant frequency shift due to viscous liquid loading. In the simulation, it is assumed that all the resonators have 2 μm thickness and 300 μm×300 μm electrode area; three different liquids (water, acetone, and olive oil) were chosen as the liquid loadings; and different tilt c-axis angles for both ZnO FBARs and AlN FBARs have been examined. It was found that the sensitivities of shear mode resonators to the three liquid loading are very close, and do not change much with the c-axis tilt angle with a value rang from 0.91e-3 to 0.97e-3 (kg m-3 Pa·S)-0.5 for ZnO FBARs and from 1.12e-3 to 1.13 e-3 (kg m-3 Pa·S)-0.5 for AlN FBARs. When the resonator's mechanical quality factor (Q) is changed from 50 to 10 000, viscosity sensitivities are almost same. However, Q has a great effect on resonator impedance; and if Q is too low or the viscosity of the liquid is high, the maximum phase angle of the resonator will be less than 0, which makes excitation of the oscillation difficult if an oscillator circuit is used for sensor measurement. The results can be used for design and application of ZnO or AlN FBARs to monitor liquid viscosity. [ABSTRACT FROM AUTHOR]

Microscale 1-3-type-like magnetoelectric (ME) composites with ferromagnetic microstrips laterally embedded in a piezoelectric ceramic substrate were fabricated by a dice-and-insert method. Mechanically sliced microstrips of Li/Ta-modified (K,Na)NbO3 lead-free ceramics and CoFe2O4 ceramics were used as the piezoelectric and piezomagnetic phases, respectively, which were inserted into each other and bonded together by epoxy. The ME properties of such 1-3-type-like composites with piezoelectric substrates were verified. The maximum ME coefficient was found to vary with the strip size, substrate thickness, and thickness of epoxy bonding layers. A maximum value of 48 mV/(cm·Oe) was achieved. In addition, a special anisotropy was obtained in the present lateral 1-3 type ceramic composites and made it have potential applications in detecting magnetic field directions. [ABSTRACT FROM AUTHOR]

Lead-free piezoelectric xLiNbO3–(1-x)(K0.52Na0.58)NbO3 (LKNN) (x=0, 0.04, 0.06, and 0.08) thin films on Pt/Ti/SiO2/Si(100) substrates were prepared by a sol-gel method. The effects of the Li substitution content on the crystal structure, microstructure, and electrical properties of LKNN films were investigated. The Li substitution leads to a remarkable improvement in the piezoelectric properties of the films. The LKNN film with an optimized Li substitution of x=0.06 showed a high local effective piezoelectric coefficient d33* of 192 pm/V, which is comparable to the piezoelectric performance of Pb(Zr,Ti)O3 films. An enhanced ferroelectricity was also obtained in the x=0.06 LKNN film, with a remnant polarization of 9.7 μC/cm2 and a coercive field of 36.5 kV/cm. Furthermore, an in-depth analysis of the leakage current characteristics of the LKNN films was also conducted in this study. [ABSTRACT FROM AUTHOR]

Microscale 1–3-type piezoceramic/epoxy composites using Li/Ta-modified (Na,K)NbO3 (NKN-LT) lead-free piezoelectric ceramics were fabricated via a modified dice-fill method, by which the NKN-LT ceramic rods were miniaturized to a lateral width of 150 μm with an aspect ratio (height/width) higher than 3.5. The piezoelectric properties of the 1–3 composites as a function of ceramic volume fraction were measured and compared with theoretical predictions. In addition to a high electromechanical coupling coefficient (kt∼50%) and low acoustic impedances (Z∼10 Mrayls), the developed composites show a clear single thickness mode with a high resonance frequency over 3.5 MHz. The present Pb-free piezocomposites are suitable for medical imaging devices embedded in the human body. [ABSTRACT FROM AUTHOR]

Anatase titania-coated bismuth ferrite nanocomposites (BiFeO3/TiO2) have been fabricated via a hydrothermal approach combined with a hydrolysis precipitation processing. Analysis of the microstructure and phase composition reveals that a core-shell BiFeO3/TiO2 structure can be formed, which results in a significant redshift in the UV-vis absorption spectra as compared to a simple mechanical mixture of BiFeO3–TiO2 nanopowders. The core-shell structured BiFeO3/TiO2 nanocomposites exhibit higher photocatalytic activity for photodegradation of Congo red under visible-light (λ>400 nm) irradiation, which should be attributed to the enhancement of the quantum efficiency by separating the electrons and holes effectively. The obtained BiFeO3/TiO2 nanocomposites can be used as potential visible-light driven photocatalysts. [ABSTRACT FROM AUTHOR]

Coarse (about 1 μm) and fine (about 100 nm) Bi2Te3 particles were synthesized by mechanical alloying for different times, respectively. Their mixtures at different ratios were consolidated by spark plasma sintering to produce nano-/microstructured composites with the same chemical compositions. The Seebeck coefficient was significantly enhanced by addition of fine particles through the potential barrier scattering. The electrical resistivity increased rapidly when the weight fraction of fine particles exceeded about 60%, probably due to an effect similar to percolation phenomenon. However, the thermal conductivity was reduced almost linearly with increasing fraction of fine particles. Because of the combined effects of the potential barrier scattering, nonlinear change in electrical property and linear change in thermal transport property, a peak value of dimensionless figure of merit (ZT) was achieved for the sample containing 60% fine particles. This study demonstrated the possibility to enhance ZT value by introducing nonuniform microstructures even without changing chemical compositions. [ABSTRACT FROM AUTHOR]

Tetragonal Nb-doped Pb(Zr0.3Ti0.7)O3 (PNZT) films with a lead oxide seeding layer were deposited on the Pt(111)/Ti/SiO2/Si(100) substrates by sol-gel processing. The as-grown PNZT films with thicknesses ranging from about 0.08 to 0.78 μm show highly a-axis preferential orientation, and their ferroelectric and piezoelectric properties improved with increasing film thickness. Due to the combined effects of Nb doping and a-axis texturing as well as reduced substrate constraint, a high d33 constant up to 196 pm/V was obtained for PNZT film at 0.78 μm in addition to a large remnant polarization of 69 μC/cm2. This well a-axis-oriented PNZT films on platinized Si with a high piezoresponse are suitable for the fabrication of microelectromechanical devices. [ABSTRACT FROM AUTHOR]

1–3 connectivity lead zirconic titanate (PZT)/epoxy composite thick films containing fine-scale and high aspect ratio PZT pillars (40 μm sectional width, 40 μm spacing, and 5.5 aspect ratio) were obtained by a modified dice and fill method. The composite thick film works at a high frequency >7 MHz with a clear and uncoupled thickness mode, together with a relatively high electromechanical coupling coefficient (kt=56.4%), low acoustic impedance (Z=7.8 Mrayls), and low mechanical Qm (3.3). High piezoelectric coefficient (d33=332 pC N-1) along with reduced dielectric constant ([variant_greek_epsilon]r=105) endowed the composite films an enhanced piezoelectric voltage coefficient g33 value of 357×10-3 m2/C, which is required to increase the receiving voltage sensitivity. The present piezocomposite thick film with microscale ordered structure is promising for high-frequency ultrasonic transducers. [ABSTRACT FROM AUTHOR]

(Bi1/2Na1/2)TiO3–(Bi1/2K1/2)TiO3 (BNT-BKT) ceramics as a promising candidate for lead-free piezoelectric ceramics were studied with a special emphasis on the compositional dependence of piezoelectric and ferroelectric properties. One mole percent excess Bi was added to compensate for the volatilization of Bi3+ ions during sintering, which was found to be effective in improving the piezoelectric properties of the resultant BNT-BKT ceramics. The piezoelectric, ferroelectric, and dielectric properties of the Bi-compensated BNT-BKT ceramics were investigated and discussed in relation to the morphotropic phase boundary that is close to the composition range of 20–24 mol % BKT. The maximum piezoelectric constant d33 (207 pC/N) and electromechanical coupling factor kp (35%) were obtained at the compositions of 23% and 20%, respectively. [ABSTRACT FROM AUTHOR]

CoSb3-xTex(x=0.05-0.3) skutterudite polycrystals with an average grain size of 160 nm were fabricated by mechanical alloying combined with spark plasma sintering. The variation of lattice parameter with Te content indicates that the solution limit of Te was x=0.15, above which the impurity phases of Te, CoTe2, and CoSb2 appeared, and the matrix cracked above 500 °C. All samples behaved as degenerate semiconductors. The forbidden energy gap was estimated to be 0.047 eV from the temperature corresponding to the occurrence of intrinsic excitation, which is in good agreement with Singh’s theoretical calculation (0.05 eV) [D. J. Singh and W. E. Pickett, Phys. Rev. B 50, 11235 (1994)]. The CoSb2.85Te0.15 sample had the highest power factor and the lowest thermal conductivity, resulting in the highest thermoelectric figure of merit, ZT=0.93 at 547 °C. The role of Te substitution in enhancing thermoelectric properties is discussed in relation to the bipolar diffusion mechanism. [ABSTRACT FROM AUTHOR]

Ta-doped Ti1-xTaxCoSb (0≤x≤0.08) half-Heusler compounds were synthesized by melting and annealing process. Their thermoelectric properties were studied in the temperature range of 300–900 K. The Ti1-xTaxCoSb compounds exhibit negative Seebeck coefficients with considerably large absolute values. With increasing Ta substitution, the electrical conductivity was greatly increased, but the thermal conductivity was reduced. Because of the combined effects of increased electrical conductivity and reduced thermal conductivity, the thermoelectric performance of Ti1-xTaxCoSb alloys was apparently improved by doping Ta. The dimensionless figure of merit of 0.3 was obtained for Ti0.92Ta0.08CoSb compound at 900 K. This value is about ten times larger than that of the undoped TiCoSb compound. [ABSTRACT FROM AUTHOR]

A pseudo-1-3-type multiferroic composite consisting of Pb(Zr,Ti)O3 (PZT) rod array (with base) and Terfenol-D/epoxy matrix was prepared by the dice-and-fill technique. Simple series and parallel mixture rules well described the measured dielectric and piezoelectric constants. Large magnetoelectric coefficients were observed in the pseudo-1-3-type composite, e.g., over 300 mV/cm Oe below 40 kHz and over 4500 mV/cm Oe at resonant frequency. The magnetoelectric response strongly depends on the magnetostrictive behavior of the matrix and the volume fraction of PZT rods, which gives us two convenient ways to modify their magnetoelectric response. For this pseudo 1-3-type multiferroic composite, the remarkable magnetoelectric response and well-developed fabrication technique are advantageous for their practical applications in piezoelectric-magnetoelectric multifunctional devices and large bandwidth magnetic sensors. [ABSTRACT FROM AUTHOR]

Two channels of the conductance G exist in cold-pressed powder compacts of CrO2/(CrO2/Cr2O3), where two types of granules have different coercivities. One of the channels is the spin-dependent intergranular tunneling conductance, and the other one is the spin-independent higher-order inelastic hopping conductance. The conductance is mainly related with the spin-dependent tunneling channel at low temperature. A large low field tunneling magnetoresistance (TMR) of 30.4% is achieved in 950 Oe field at 2 K. The reason is the relative orientation of the magnetization that tends to be antiparallel between the two coercivities. Field dependence of the tunneling magnetoresistance shows two better-separated peaks than that of CrO2 powder compact. The results suggest that the introduction of CrO2/Cr2O3 improves low field sensitivity, TMR, and switching characteristics. [ABSTRACT FROM AUTHOR]

Lead zirconate titanate [Pb(ZrxTi1-x)O3, PZT] thin films with various compositions, whose Zr/Ti ratio were varied as 40/60, 48/52, 47/53, and 60/40, were deposited on Pt(111)/Ti/SiO2/Si substrates by sol-gel method. A seeding layer was introduced between the PZT layer and the bottom electrode to control the texture of overlaid PZT thin films. A single perovskite PZT thin film with absolute (100) texture was obtained, when lead oxide was used as the seeding crystal, whereas titanium dioxide resulted in highly [111]-oriented PZT films. The dielectric and ferroelectric properties of PZT films with different preferential orientations were evaluated systemically as a function of composition. The maximums of relative dielectric constant were obtained in the morphotropic phase boundary region for both (100)- and (111)-textured PZT films. The ferroelectric properties also greatly depend on films’ texture and composition. The intrinsic and extrinsic contributions to dielectric and ferroelectric properties were discussed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Lead-free piezoelectric xLiNb[O.sub.3]-(1-x)([K.sub.0.52][Na.sub.0.58])Nb[O.sub.3] (LKNN) thin films on Pt/Ti/Si[O.sub.2]/Si(100) substrates are prepared by sol-gel method and the effects of the Li substitution content on the crystal structure, microstructure and electrical properties of LKNN films are examined. The Li substitution has led to a remarkable improvement in the piezoelectric properties of the films.

A modified dice-fill method was employed to fabricate the microscale 1-3-type piezoceramic/epoxy composites using Li/Ta-modified (Na,K)Nb[O.sub.3] (NKN-LT) lead-free piezoelectric ceramics. The developed composites showed a high electromechanical coupling coefficient, low acoustic impedances and a clear single thickness mode with a high resonance frequency over 3.5 MHz.

Anatase titania-coated bismuth ferrite nanocomposites (BiFe[O.sub.3]/Ti[O.sub.2]) are prepared through a hydrothermal approach combined with a hydrolysis precipitation processing. The core-shell structured BiFe[O.sub.3]/Ti[O.sub.2] nanocomposites have displayed higher photocatalytic activity for photodegradation of Congo red under visible-light irradiation, which is attributed to the increase in the quantum efficiency by separating the electrons and holes effectively.

The mechanical alloying for different times were employed to synthesize the coarse and fine [Bi.sub.2][Te.sub.3] particles. The result obtained demonstrated the possibility to enhance peak value of dimensionless figure of merit (ZT) value by introducing nonuniform microstructures without changing chemical compositions.

A sol-gel processing method is used to deposit tetragonal Nb-doped Pb([Zr.sub.0.3][Ti.sub.0.7])[O.sub.3] (PNZT) films with a lead oxide seeding layer on the Pt(111)/Ti/Si[O.sub.2]/Si(100) substrates. The well developed a-axis-oriented PNZT films on platinized Si with a high piezoresponse could be adapted to fabricate microelectromechanical devices.

The piezoelectric and ferroelectric properties, dielectric behavior and microstructure of Bi-compensated ([Bi.sub.1/2][Na.sub.1/2])Ti[O.sub.3]-([Bi.sub.1/2][K.sub.1/2])Ti[O.sub.3] (BNT-BKT) lead-free ceramics are examined. The maximum piezoelectric constant [d.sub.33] and electromechanical coupling factor are obtained at the compositions of 23% and 20%, respectively.

The effect of Ta doping on the thermoelectric properties of half-Heusler compounds [Ti.sub.1-x][Ta.sub.x]CoSb is investigated. Ta substitution increases the electrical conductivity but decreases the thermal conductivity, while this property improves the thermoelectric performance of the Ta doped [Ti.sub.1-x][Ta.sub.x]CoSb alloy.

The magnetic and transport properties of CrO2/(CrO2/Cr2O3) powder compact are studied. The results suggest that introduction of CrO2/Cr2O3 improves low field sensitivity, tunneling magnetoresistance and switching characteristics.

Lead zirconate titanate thin films with various compopsitions were deposited on Pt(111)/TiSiO2 substrates by sol-gel method. The seeding layers were more effective in growing the more effective in growing the highly textured PZT thin films.