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Making embedded memory symmetric provides the capability of memory access in both rows and columns, which brings new opportunities of significant energy and time savings if only a portion of data in the words need to be accessed. This work investigates the use of ferroelectric field-effect transistors (FeFETs), an emerging nonvolatile, low-power, deeply-scalable, CMOS-compatible transistor technology, and proposes a new 3-transistor/cell symmetric nonvolatile memory (SymNVM). With ~1.67x higher density as compared with the prior FeFET design, significant benefits of energy and latency improvement have been achieved, as evaluated and discussed in depth in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we report the electrate properties of ferroelectric polymer PVDF and its composites with three different fillers as ceramic-BaTiO3, metallic semiconductor-ZnO and metallic-TiO2 in PVDF matrix. Each type of PVDF composites thin films with 2wt%, 6wt% and 10wt% of fillers were synthesized by solution casting techniques using dimethylformamide (DMF) as solvent. The XRD pattern confirms the formation of tetragonal perovskite structure of ferroelectric retaining 13-phase and shows proper mixing of fillers interstitially and improved crystallinity with increase of composition in the PVDF matrix. Electric poling effect on the pristine PVDF and its composites were studied by measuring the relative change in strain capacitance using LCR meter. The PVDF and its composites have shown systematic oscillations in strain capacitance with applied electric field. The variation in the strain capacitance is explained in terms of dynamics of dipole pinning and electrostriction induced strain capacitance. [ABSTRACT FROM AUTHOR]

Few Korteweg-de Vries-Burgers (Kdv-B) equations were arise in many fields. Among these all, Kdv-B equation that describes ferroelectricity were considered in this paper. The capacity of battery for electronic applicants are one of the selling point, Kdv-B equations were important as this help to study the ferroelectricity, and ferroelectricity decides charging capacity of various materials. Here, to help researcher to decide which material to be more suitable to produce battery, Kdv-B equations need to be solved. In this paper, we transformed Kdv-B by using method of symmetry reduction. After some reductions, some differential equations in lower order will be found. And by compared to exist literature, a big class of solution can be found. Furthermore, Short Pulse Equation (SPE) which represent propagation of ultra-short light pulses in silica optical fibres, also were analysed by using Lie symmetry. [ABSTRACT FROM AUTHOR]

In this paper, we provide a complete mathematical model of the phenomenon of optical bistability (OB) resulting from the degenerate two-wave mixing (TWM) process of laser beams interacting with a single nonlinear layer of ferroelectric material. Starting with the electromagnetic wave equation for optical wave propagating in nonlinear media, a nonlinear coupled wave (CW) system with both self-phase modulation (SPM) and cross-phase modulation (XPM) sources of nonlinearity are derived. The complete CW system with full nonlinearity is solved numerically and a comparison between both the cases of with and without SPM at various combinations of design parameters is given. Furthermore, to provide a reliable theoretical model for the OB via TWM process, the results obtained theoretically are compared with the available experimental data. We found that the nonlinear system without SPM fails to predict the bistable response at lower combinations of the input parameters. However, at relatively higher values, the solution without SPM shows a reduction in the switching contrast and period in the OB response. A comparison with the experimental results shows better agreement with the system with full nonlinearity. [ABSTRACT FROM AUTHOR]

In the present paper, by modifying two sublattice pseudospin lattice coupled-mode model (PLCM) containing third and fourth-order phonon anhannonic interaction terms by adding extra spin-lattice interaction, direct spin-spin interactions terms, and electric field term is considered for Rochelle salt (RS) crystal By using double time-temperature dependent Green's function method, Dyson equation theoretical expressions for ferroelectric soft mode frequency, dielectric constant and dielectric loss tangent have been derived for Rochelle salt By fitting various model values of physical parameters, thermal variations for ferroelectric mode frequency, dielectric constant and dielectric tangent loss have been obtained for Rochelle salt. For validation of t heoretical results have been compared with the experimental results. [ABSTRACT FROM AUTHOR]

Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) is a basic type of transistor to be used as a switch since 1959. Since then, the successful of MOSFET is due to good properties between silicon and silicon dioxide. The reduction of silicon oxide thickness provide further enhancement in device performance. At 90 and 65 nm technology nodes, the gate oxide could not be scaled anymore due to the direct tunneling effect resulting significant increase of leakage current. At 45 nm the high-k + metal gate has been introduced. Recently, the ferroelectric effect material is introduced which significantly reduce the gate leakage current. This paper review the evolution of gate dielectric scaling from the era of silicon dioxide to high-k + metal gate and ferroelectric effect material. [ABSTRACT FROM AUTHOR]

Through an extensive literature review the cation substitution effect on multiferroic behavior of BiFeO3 commonly known as BFO has been analyzed. A deep introspection has been made to find the doping effect on its structural, micro structural and electrical microstructure which consequently changes its dielectric, ferroelectric, electrical and magnetic, multiferroic and other properties. A systematic analysis has been made to find how the doping at both A and B site of its ABO3 perovskite structure causes a compositional driven structural change resulting in improved multiferroic properties. In this review attempt has been made to reveal the physics behind the major issues in BFO like single phase preparation, oxygen ion vacancy, leakage current, suppressed latent magnetization in spin cycloid, low value of electrical polarization, low magnetoelectrical coupling, microwave properties and how these issues have been addressed so far by modifying BFO. Many theoretical and experimental investigations on BFO, modified BFO and its composite establish a competitive mechanism due to which improved ferroelectricity is achieved at cost of magnetism or improved magnetism is achieved at the cost of ferroelectricity. Thus, the desirable multiferroic properties have not yet achieved completely to make the material device ready. Finally, a detailed analysis have been made to explore all possible applications of these materials taking into all the physical parameters achieved so far in these materials to make them truly multifunctional and on the basis of this study, we have proposed how to modify the BFO to achieve a new generation multifunctional material. [ABSTRACT FROM AUTHOR]

The Dynamic Landau-Khalatnikov (LK) model was modified to calculate polarization hysteresis curve for Zinc Oxide (ZnO) material. Ferroelectric polarization hysteresis of Zinc Oxide (ZnO) were measured by using Sawyer-Tower circuit. Landau Khalatnikov modified model was fitted to experimental data. R-Weighted Pattern (Rwp) factor was used to evaluate the precision of the model compare to experimental data. The results showed that the modified model is in a good precision compare to experimental data with Rwp< 10%. [ABSTRACT FROM AUTHOR]

CaxBa1-xNb2O6 (CBN) ceramics with tetragonal tungsten bronze (TTB) structures are very attractive from academic and technological fronts due to their outstanding ferroelectric properties. Hence, CBN ceramics were prepared by high temperature solid state reaction technique in this work. The phase formation, microstructure and dielectric properties of the prepared samples were investigated by X-ray diffraction, scanning electron microscope and impedance analyzer, respectively. The X-ray analysis confirms the partially filled tetragonal tungsten bronze (TTB) structure. The scanning electron micrographs provide information related to the morphology and grain size distribution of the samples. The dielectric and ferroelectric properties of CaxBa1-xNb2O6 (x= 0, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4) ceramics were also measured, and they have been found to be strongly processing-dependent. The frequency dependence of the dielectric constant (e) of the samples have been discussed. Detailed analysis of the structural and dielectric properties suggests that these samples have undergone a phase transition well above the room temperature. DC resistivity studies on the samples are marked by a response of positive temperature coefficient of resistivity (PTCR) in all the compositions. [ABSTRACT FROM AUTHOR]

Sol-gel erbium doped barium titanate (Ba0.7Er0.3TiO3) thin films have been spun-coated on SiO2/Si and Pt/TiO2/SiO2/Si substrates, then characterized using X-ray diffractometer (XRD) and Sawyer-tower circuit to study the crystallinity and ferroelectric hysteresis loop, respectively. In XRD, lattice geometric equations have been applied to expose the lattice parameters for Ba0.7Er0.3TiO3 thin film, which show that the films hold tetragonal perovskite structure at room temperature. In addition, size-strain plot has been employed to the scanned patterns, which reveals that the films are nano-crystallized. The results obtained via sawyer-tower circuit confirm the ferroelectricity nature within the Ba0.7Er0.3TiO3 thin films, and the remnant polarization increase with increasing of film thickness. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) is a polymer with unique characteristics i.e. piezoelectric and ferrroelectric properties. Piezoelectric propertiesof PVDF are determined by the fraction of β-phase structure. Several optimization methods have been developed to improve the piezoelectric properties of PVDF. One of our research efforts is to improve the piezoelectricity of PVDF by electric poling with high electric field 2G V/m. The application of high electric field performed on PVDF films with a thickness of 1 μm. Each sample was made with a deep coating method, with annealing temperature 70°C-110°C. Based on the XRD characterization, we have obtained value of β-fraction of samples after poling are: 56%, 61%, 77%, 81% and 83%, respectively. Therefore, high electric field poling has been able to improve the piezoelectric properties of PVDF films. The PVDF with good piezoelectric properties are potential can did a tes for piezoelectric sensors and actuators devices. [ABSTRACT FROM AUTHOR]

In this work, we have studied the structural, magnetic and ferroelectric properties of Eu1-xYxMnO3 (x=0.25) sample prepared by solid state route. From magnetization measurement, we observed two magnetic transitions at T=47K and 22K. Temperature dependence dielectric constant (ε) shows transition at ~22K but not at higher magnetic ordering temperature, and as a function of field, there occurs a shift of ε at higher temperature. Also in the pyroelectric currrent measurement we observed transitions ~20K which is very close to the magnetic transitions. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PDVF), one of the best electrically active polymer material & an interesting candidate to address the electrical control of its functional properties like ferroelectricity, piezoelectricity, pyroelectricity etc. In the current work, with the help of spin coater and DC magnetron sputtering techniques, semi-crystallized PVDF thin films prominent in alpha phase is prepared in capacitor like structure and their electrical characterization is emphasized. In current-voltage (I-V) and resistance-voltage (R-V) measurements, clear nonlinearity and resistance switching has been observed for films prepared using 7 wt% 2-butanone and 7 wt% Dimethyl Sulfoxide (DMSO) solvents. [ABSTRACT FROM AUTHOR]

Single crystals of Urea Succinic Acid (USA) were grown by slow cooling technique. The crystalline system was confirmed by powder X-ray diffraction. The metastable zonewidth were carried out for various temperatures i.e., 35°, 40°, 45° and 50°C. The induction period is experimentally determined and various nucleation parameters have been estimated. [ABSTRACT FROM AUTHOR]