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Lead zirconate titanate (PZT) stacks that have an interdigital internal electrode configuration are tested and significant reductions in piezoelectric and dielectric responses are observed during the cycling depending on the measuring condition. The results have shown the feasibility of using a semibipolar mode to drive a PZT stack under a mechanical preload and also display the potential fatigue and damages of the stack in service.

Highly oriented Pb([Fe.sub.1/2][Ta.sub.1/2])[O.sub.3] (PFT) film is prepared on conducting [La.sub.0.67][Sr.sub.0.33]Co[O.sub.3] coated (100) MgO substrate by using pulsed laser deposition method. A large shift in dielectric maximum temperature is observed when compared to bulk counterpart that is due to misfit strain across substrate-bottom electrode-film interface and in plane compressive strain in the film.

Monte Carlo method is used for examining magnetic behaviors of Fe nanowires grown on 4 [degree] miscut Si(111) substrate with Pb buffer layers. The exchange coupling between the overlapping islands is shown to be responsible along with the magnetostatic energy for the ferromagnetic ordering of high coverage Fe chains at room temperature.

A first-principles based model is described and validated for the nonlinear piezoelectric response of an electroelastic energy harvester. The analysis has highlighted the importance of modeling inherent piezoelectric nonlinearities that are not limited to higher order elastic effects but has also included nonlinear coupling to a power harvesting circuit.

The effects of the strain induced by ferroelectric poling on the transport and magnetic properties of [La.sub.7/8][Ba.sub.1/8]Mn[O.sub.3] (LBMO) thin films epitaxially grown on ferroelectric 0.67Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.33PbTi[O.sub.3] (PMN-PT) single-crystal substrates are examined. The effects of polarization reversal on the transport properties of the LBMO film have shown that the ferroelectric-poling-induced strain effects have dominated over the ferroelectric field effects in the LBMO/PMN-PT structure.

The anionic framework of the crystal is preserved even during the replacement of cationic sublattice with a different metal ion via reversible place exchange in ionic nanocrystals. This method has ensured that compositional interfaces within the heterostructure are conserved throughout the transformation when it is applied to nanoheterostructures.

Several experimental, as well as theoretical studies are conducted to explain the polarization switching taking place in the unfatigued soft lead-zirconate-titanate ceramic. The polarization is shown to be highly dependent on the time and the applied field.

Several studies are conducted to explain the impact of the tetragonal distortion on ferroelectric, as well as the piezoelectric properties of the La-doped BiFe[O.sub.3]uPbTi[O.sub.3] ceramics. The domain switching of the ceramics is shown to be highly dependent on the c/a ratio.

The Fourier transform infrared photoluminescence spectroscopy technique is employed to explain the photoluminescence and the emission properties exhibited by the PbS quantum dots dispersed on semi-insulating GaAs. These dots are shown to lead to an enhancement of the emission features of the GaAs substrate.

The possible mechanisms of phonon scattering by nanostructures and defects in PbTe-X (X = 2%Sb, Bi, or Pb) thermoelectric materials systems are examined. The particle-induced local elastic perturbations have interfered with the phonon propagation pathway, thereby contributing to the reduction in lattice thermal conductivity and increasing the overall thermoelectric figure of merit.

The stability of various crystallographic phases of (1-x)BiFe[O.sub.3]-xPbTi[O.sub.3] is studied as a function of composition and temperature. The comparison between the bon lengths between oxygen and other cations has shown that the very high c/a ratio in the tetragonal phase of the system is linked with the covalency effects for bonding between both A and B site cations with oxygen.

Luciferase (Luc8) is used as a template to direct the synthesis of near-infrared (NIR) light emitting PbS quantum dots (QDs) at ambient conditions to form a Luc8-PbS nanocomplex. The addition of the substrate coelenterazine has helped in nonradiatively transferring the energy produced by Luc8 to PbS QDs via bioluminescence resonance energy transfer (BRET) and has enabled the complex to emit NIR light.

The generation of charge in thin piezoelectric structures is measured and modeled under sinusoidal hydrostatic pressure and has also shown the domination of the subsequent thermally induced pyroelectric effect on the response in the smallest samples. The analysis of the piezoelectric and pyroelectric charge response has major impact on the design and functional behavior of small-scale piezoelectric devices.

Inherent excitonic luminescence in metal halide (MH) is dominated by a very high light-emitting mechanism, which is demonstrated by using improved films of MH produced by two simple methods. Inherent excitonic luminescence in MH is very good for applications in exciton-based light-emitting devices, particularly in shorter-wavelength devices than the traditional, nonexcitonic ones as it is only MH that has included many compounds with large band gap and large exciton binding energies.

A combination of the x-ray diffraction and scanning electron microscope techniques is employed to analyze the magnetoimpedance and magnetodielectric properties of single phase 45PMN-20PFW-35PT ceramics.

The article explains the abnormal dielectric relaxation phenomenon that is normally exhibited by the different Pb[Zr.sub.0.38][Ti.sub.0.62][O.sub.3] multilayers. The results demonstrate that the applied dc bias can be easily employed for changing the dielectric loss of the multilayers.

The article presents a newly devised dc magnetoelectric sensor based on the direct coupling of Lorentz force effect in aluminum strip with transverse piezoelectric effect in 0.7Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.3PbTi[O.sub.3] single-crystal plate. The applications and the effectiveness of the sensor is also determined.

A giant magnetoelectric (ME) effect observed in a current-to-voltage (I-to-V) conversion device formed by sandwiching a PZT piezoelectric cymbal transducer between an NdFeB magnet and a Fe-core solenoid is reported. The observed ME effect and the resulting I-to-V conversion in the device is demonstrated by a physical model based on the combination of electromagnetomechanics in the magnet-solenoid assembly and amplified piezoelectricity in the cymbal transducer.

A transient absorption and luminescence study is used for addressing the charge separation, recombination and regeneration reactions at nanostructured metal oxide/PbS quantum dot/organic hole conductor heterojunctions. The studies have shown a correlation between the PbS particle size and the yield of charge separation at PbS/Sn[O.sub.2] interfaces, with a smaller PbS particle radius that has resulted in a higher yield of charge separation.

A sputtering method is used for preparing anatase Nb-based Ti[O.sub.2] transparent conducting oxide on GaN(0001) surfaces. The studies have shown that Nb-doped T[O.sub.2] is a good material for use as transparent electrodes in GaN-based light emitting diodes (LEDs), since reflection at the electrode/GaN boundary is suppressed, enhancing the external quantum efficiency of blue LEDs.

The ferroelectric, dielectric, elastic piezoelectric and electromechanical properties of tetragonal Pb([In.sub.1/2][Nb.sub.1/2])[O.sub.3]-Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PIN-PMN-PT) crystals are examined. The studies have shown that tetragonal PIN-PMN-P crystals have displayed broader temperature usage range and higher thermal/electric field stability, with improved coercive field and mechanical quality factor in contrast to [001] oriented domain engineered rhombohedral crystals.

The effect of local surface potential distribution on its relaxation in the polycrystalline ferroelectric thin films is analyzed. The results have shown that the surface potential distribution has affected the reliability of bit signal on the memory devices.

The formation of various isostructural inorganic-organic hybrid ferroelectric compounds from the aggregation of the [[Pb[I.sub.3]].sub.delta] chains directed organic cations to Kagome-shaped tubular architecture is discussed. The large spontaneous polarizations exhibited by these compounds are also explained.

Several numerical simulations are conducted to determine the pyroelectric coefficients of the laminate composites under the short circuit condition. The various conditions or mechanisms that lead to the enhancement of the discussed effect are also explained.

The temperature dependence of the visible fluorescence lines of large Pb[F.sub.2] nanocrystals codoped with [Er.sup.3+] and [Yb.sup.3+] ions is studied. The studies have shown that the fluorescence is affected both by the near-field optical distribution and by temperature variations.

The crystallinity, ferroelectric, ferromagnetic and magnetodielectric properties of epitaxial bilayered films consisting of [La.sub.0.6][Sr.sub.0.4]Mn[O.sub.3] (LSMO) and 0.7Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.3PbTi[O.sub.3] (PMN-PT) layers prepared on LaNi[O.sub.3] coated LaAl[O.sub.3] (001) single crystal substrates by pulsed laser ablation methods are examined. The dielectric properties of these heterostructures have provided a possible role of elastic strain mediated magnetoelectric coupling behind the magnetodielectric effect in addition to the impact of rearrangement of the interfacial charge carriers under an applied magnetic field.

The article explains the various piezoinductive effects that are observed in a piezoelectric ring with nonmagnetic conductive metal electrodes on its inner, as well as outer surfaces. The effects are shown to be widely used in numerous magnetic field sensing and modulation applications.

The article studies the monolithically integrated bifunctional frontplane element based on a composite foil of piezoelectric ceramic lead titanate nanoparticles embedded in ferroelectric poly polymer matrix. Findings highlight multifunctional frontplanes for large area electronic surfaces.

The spectroscopic and fluorescence properties of the [Pr.sup.3+] doped low-energy phonon and nonhygroscopic chloride and bromide single crystals K[Pb.sub.2][Cl.sub.5] and CsCd[Br.sub.3] are described. The results of fluorescence decays and emission spectra measurements have helped in understanding the emission and gain cross sections of the main midinfrared (mid-IR) emission transitions of crystals.

The dependence of the longitudinal flexural resonance frequency shift of a [(Pb[Mg.sub.1/3][O.sub.3]).sub.0.63][(PbTi[O.sub.3]).sub.0.37] (PMN-PT) piezoelectric microcantilever sensors (PEMS) displaying a Young's modulus-change mechanism on its thickness and length is examined. It is shown that the resonance frequency shift caused by Young's modulus change in the piezoelectric layer is more than 300 times larger than that is expected from the mass change.

The ferroelectric properties of Pb([Zr.sub.0.5][Ti.sub.0.5])[O.sub.3] (PZT) nanowires are examined by using Landau-Ginzburg-Devonshire theory, which has considered the nanowire size, polarization gradient, temperature and axis stress. The results have shown that an unusual thermal fluctuation is present in PZT nanowires with small diameter.

The observation of stripe domains in PbTi[O.sub.3] thin films by using standard x-ray diffraction analysis at room temperature is described. The simulations have shown that random variations in size of the domains have affected the separation of the diffuse scattering peaks from that of the specular reflection.

The conformal deposition of both Ru[O.sub.2] electrodes and Pb[Zr.sub.x][Ti.sub.1-x][O.sub.3] (PZT) capacitors in submicron Si trenches through the same in situ liquid source mist processing is described. The studies have shown that a single inexpensive processing has produced fully electroded dynamic random access memory trenched capacitors with high aspect ratios and commercial electrical performance.

The effects of compressive stress on the ferroelectric properties of Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PMN-PT) ceramics are examined. The results are interpreted by the non-180 [degree] ferroelastic domain switching processes and the stress induced decrease in the switchable part of domains.

The writing and reading characteristics of ferroelectric domain bits on a preferentially (111)-oriented lead zirconate titanate (PZT) thin film on (111) Pt/Ti[O.sub.2]/Si[O.sub.2]/Si substrate grown by eclipse pulsed laser deposition (PLD) is described. The small roughness of PZT thin films has made a negligible effect on electron force microscope images, which has given the enhanced resolution for the minimum ferroelectric bit size.

Local low energy-loss functions (ELFs) of chemical ordered nanodomains in relaxor Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3] (PMN) are obtained by using Kramers-Kronig analysis of experimental electron low energy-loss spectra. The studies have shown that the Nb 4d-O 2p hybridization is increased through ferroelectric transition, which has made the O 2p collective excitation energy upper shift in ELF, while Mg, also as the B-site ion, has presented no covalent bonding effect with O.

The dielectric and ferroelectirc properties of (1-x)Pb([Mg.sub.1/3][Nb.sub.2/3])[(O.sub.3]-(x)PbTi[O.sub.3] ((1-x)PMN-(x)-PT) (x=0.1-0.4) ceramics are measured under compressive stress applied perpendicular to the electric field. The influences of the stress applied in the perpendicular direction to the electric field are opposite to those of the parallel stress.

The microhardness enhancement of p-type PbTe alloys with higher hole concentrations is analyzed. The mechanisms correlating between mechanical and electronic properties of PbTe based alloys have served as guidelines for searching potential candidates, obtaining both thermoelectric potential and mechanical stability for thermoelectric applications.

A combination of photoelectron (PE) spectra and density functional theory studies is conducted to explain the preparation and properties of the pyridyl-lead, [[[Pb.sub.m]-pyridyl].sup.-] (m = 1-4) complexes. These compounds are shown to exhibit a closed-shell electron ground-state structure of the singlet state.

The electronic properties of assemblies of heterostructured nanocrystals are examined and a novel approach is described for doping of nanocrystal solids through the intraparticle charge transfer. Au-PbS core-shell nanostructures are chosen as a model system for studying coupling effects between strongly confined metal and semiconductor phases.

The phase transition and the phase stability in 0.68Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.32PbTi[O.sub.3] (PMN-0.32PT) single crystals under different electric fields are examined. The results have helped in understanding the phase transitions as well as the impact of the electric field on the phase transitions in PMN-PT single crystals.

The effects of Ta content on the phase transitional behavior, Raman spectrum, microstructure and dielectric, piezoelectric and ferroelectric properties of the lead-free [[([K.sub.0.458][Na.sub.0.542]).sub.0.96][Li.sub.0.04]]Nb[O.sub.3] ceramics are examined. The X-ray diffraction results have shown that the phase structure has undergone a transition from orthorhombic to tetragonal phase.

The [(110).sub.t] preferred oriented PbZr[O.sub.3] (PZ) thin films grown on Pt(111)/Ti/Si[O.sub.2]/Si by sol-gel method is characterized. The slim P-E hysteresis loop is explained by [(110).sub.t] preferred orientation of PZ films and the dielectric response is described at a relatively higher frequency range.

The effect of (Sc,Ta,Ce) doping on the properties of [Bi.sub.3]TiNb[O.sub.9] (BTNO)-based ceramics is examined. The dielectric and piezoelectric properties of [Bi.sub.3][Ti.sub.0.96][Sc.sub.0.02][Ta.sub.0.02]Nb[O.sub.9]-based ceramics have displayed a very stable temperature behavior, along with a high Curie temperature, excellent piezoelectric coefficient and very low temperature coefficient of resonant frequency.

The solid solution between the antiferroelectric (AFE) PbZr[O.sub.3] (PZ) and the relaxor ferroelectric (FE) Pb([Ni.sub.1/3][Nb.sub.2/3])[O.sub.3] (PNN) is prepared by the columbite precursor method and their crystal structures, phase transformations and dielectric and thermal properties are examined. The FE phase temperature range width has increased with the increasing PNN.

Dielectric and Raman scattering experiments are used for studying polycrystalline [Pb.sub.1-x][Ba.sub.x]Ti[O.sub.3] thin films as a function of temperature. The lack of a well-defined transition temperature and the presence of broadbands in some temperature intervals above the paraferroelectric phase transition temperature have shown a diffuse-type phase transition.

The out-of-plane and in-plane x-ray diffractions are employed to explain the structural, as well as the dielectric characterizations of the relaxor/ferroelectric superlattice films Pb([Sc.sub.1/2][Nb.sub.1/2])[O.sub.3]/PbTi[O.sub.3], which are fabricated on a single-lattice scale. The superlattice structures of the films are shown to be coherent over the entire sample.

Random-access memory switches are fabricated by using 70 nm thick spun films of nonperipherally octahexyl substituted lead phthalocyanine (PbPc) molecules sandwiched between indium tin oxide (ITO) substrates and vacuum-deposited aluminum (Al) top electrodes. The bistable electrical switching effects are attributed to the existence of the depletion layer at the ITO/PbPc and exponential distribution in energy of traps in nonactive region of PbPc films.

The studies about the magnetic susceptibility of Pb([Fe.sub.1/2][Nb.sub.1/2])[O.sub.3] (PFN) below [T.sub.c] and of 0.8PFN-0.2PMW ([Mg.sub.1/2][W.sub.1/2])[O.sub.3] below [T.sub.0] are presented. The findings showed an increase indicating towards coupling between the ferroelectric and magnetic orders.