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Book Residual Ferroelectricity  Piezoelectricity  and Flexoelectricity in Barium Strontium Titanate Tunable Dielectrics

Download or read book Residual Ferroelectricity Piezoelectricity and Flexoelectricity in Barium Strontium Titanate Tunable Dielectrics written by Lauren Garten and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Loss reduction is critical to the development of Ba1-xSrxTiO3 (BST) thin film tunable microwave dielectrics. This work addresses mechanisms of loss and performance of Ba1-xSrxTiO3, such as residual ferroelectricity, enhanced flexocoupling, and dc electric field induced piezoelectricity.The presence of residual ferroelectricity --a persistent ferroelectric response above the global phase transition temperature, adds a contribution to dielectric loss from either motion of domain walls or the boundaries of micropolar regions, degrading the tunable performance over a wide frequency range. Rayleigh behavior as a function of temperature was used to track the ferroelectric behavior of BST materials through the ferroelectric to paraelectric transition temperature. The irreversible Rayleigh parameter serve as a metric for the presence of ferroelectricity because this response is dependent on the presence of domain walls, cluster boundaries or phase boundaries. Chemical solution deposited Ba0.7Sr0.3TiO3 films, with relative tunabilities of 86% over 250kV/cm at 100kHz, demonstrated residual ferroelectricity at least 65°C above the ostensible paraelectric transition temperature. The Rayleigh behavior was further corroborated with second harmonic generation, polarization-electric field hysteresis loops and the frequency dependence of the Rayleigh response. The temperature extent of residual ferroelectricity in sputtered and chemical solution deposited films and bulk ceramics was investigated as a function of chemical inhomogeneity on the A-site using electron energy loss spectroscopy. All samples showed some residual ferroelectricity, where the temperature extent was a function of the sample processing. The application of AC electric field for residual ferroelectric measurements of these samples lead to a 100% increase in loss for ac fields exceeding 10kV/cm at room temperature.The presence of residual ferroelectricity in BST also correlates to the increased flexoelectric response in these materials. Residual ferroelectricity is observed in barium strontium titanate ceramics 30°C above the global phase transition temperature, in the same temperature range in which anomalously large flexoelectric coefficients are reported. The application of a strain gradient in this temperature range was shown to lead to strain gradient-induced poling, or flexoelectric poling, enhancing the flexoelectric response. Flexoelectric poling was observed by the development of a remanent polarization in flexoelectric measurements upon the removal of the applied strain gradient. Additionally, an induced d33 piezoelectric response was observed in samples after the removal of the applied strain gradient, indicating that the polarization was realigned during flexoelectric measurements. Flexoelectric poling lead to the production of an internal bias of 9 kV/m. It is concluded that residual ferroelectric response considerably enhances the observed flexoelectric response. In order to investigate the effects of dc electric field induced piezoelectricity, metrology was designed, developed and calibrated for the measurement of the e31,f piezoelectric coefficient as a function of applied electric field and strain. This allowed for direct measurements of the field-induced piezoelectric response for Ba0.7Sr0.3TiO3 (70:30) and Ba0.6Sr0.4TiO3 (60:40) thin films on MgO and silicon. The relative dielectric tunabilities for the 70:30 and 60:40 composition on MgO were 83% and 70% respectively, with a dielectric loss of 0.011 and 0.004 at 100 kHz respectively. A linear increase in induced piezoelectricity with field to --3.0 C/m2 and --1.5 C/m2 at 110 kV/cm was observed in 60:40 BST on MgO and 70:30 BST on Si. Large and hysteretic piezoelectric and tuning responses were observed in the 70:30 BST thin films on MgO. This was consistent with the irreversible Rayleigh behavior, indicating a ferroelectric contribution to the piezoelectric and dielectric response 40°C above the global paraelectric transition temperature. This information should enable advancements in tunable dielectric components through the removal of piezoelectric resonance-based loss mechanisms.

Book Atomistic and Continuum Study of Flexoelectricity in Ferroelectric Materials

Download or read book Atomistic and Continuum Study of Flexoelectricity in Ferroelectric Materials written by Raouf Mbarki and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, we try to address some of the questions which arise while studying flexoelectricity in ferroelectric materials. 1. Most technologically-relevant ferroelectrics typically lose piezoelectricity above the Curie temperature. This limits their use to relatively low temperatures. In this dissertation, exploiting a combination of flexoelectricity and simple functional grading, we propose a strategy for high-temperature electromechanical coupling in a standard thin film configuration. We use continuum modeling to quantitatively demonstrate the possibility of achieving apparent piezoelectric materials with large and temperature-stable electromechanical coupling across a wide temperature range that extends significantly above the Curie temperature. With Barium and Strontium Titanate as example materials, a significant electromechanical coupling that is potentially temperature-stable up to 900 C is possible. 2. Piezoelectricity is a property of non-centrosymmetric crystals. In most typically used ferroelectrics, this property is lost as the temperature is increased beyond the Curie point thus strongly reducing the availability of efficient materials that can be used for high temperature energy harvesting. Flexoelectricity, as can be shown from simple symmetry arguments, is a universal and linear electromechanical coupling that dictates the development of polarization upon application of inhomogeneous strains. The implications of this phenomenon become amplified at the nanoscale. In this dissertation, we develop a molecular dynamics approach predicated on a specially tailored interatomic force-field to extract the temperature dependence of flexoelectricity. Surprisingly, we find that it, at least for Barium Titanate and Strontium Titanate nano structures, increases with temperature. Apart from cataloging this interesting observation for future use in high temperature energy harvesting, we also examine the physical mechanisms that lead to the observed temperature dependence. 3. A new theory for 180 domain wall in ferroelectric perovskite material is presented in this work. The effect of flexoelectric coupling on the domain structure is analyzed. We show that the 180 domain wall has a mixed character of Ising and Bloch type wall and that the polarization perpendicular to the domain wall is non zero though it is very small compared to the spontaneous polarization in the case of tetragonal Barium Titanate. Finally, we present the effect of the new finding on the domain wall interaction with defects in the material. 4. Pyroelectric materials generate electricity in response to change in temperature. These materials are commonly used to build temperature sensors, radiation detectors and alarm systems, among others. There are few materials that possess this property. In this work, we develop a nonlinear theoretical framework for pyroelectricity in soft materials. Using the concept of soft electrets materials, we illustrate a nonlinear relation between the Maxwell stress effect and pyroelectricity, and propose the design of a pyroelectric material whose constituents are intrinsically non-pyroelectric.

Book Ferroelectrics of Barium Titanate Type  a Bibliography

Download or read book Ferroelectrics of Barium Titanate Type a Bibliography written by Naval Ordnance Test Station (China Lake, Calif.). Research Department and published by . This book was released on 1952 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Effects of Strain on Dielectric Properties of Ferroelectric Ba0 5Sr0  5TiO3 FILM  S

Download or read book Effects of Strain on Dielectric Properties of Ferroelectric Ba0 5Sr0 5TiO3 FILM S written by Hongrui Liu and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Owing to the large electric-field-dependent permittivity, ferroelectric thin films have attracted a great deal of attention on applications in miniature tunable microwave components with high performance and cost reduction, such as phase shifters, tunable oscillators, delay lines, and antennas. These tunable devices require large change in the dielectric constant with applied field and a low loss at microwave frequencies. As one of the promising ferroelectric materials, barium strontium titanate thin film, especially Ba0.5Sr0.5TiO3 (BST) films, have raises great research interests due to its high dielectric constant, which is tunable in an external electric field, combined with relative low loss at microwave frequencies. Tunable microwave components, such as phase shifter, based on the BST films have been widely investigated. Since the polarization, the significant characterization of ferroelectrics, is very sensitive to distortion in crystal structure of ferroelectrics, strain can be effectively utilized to tailor the dielectric properties of BST films. Due to the lattice-mismatch from the substrate and various deposition conditions, epitaxial BST thin film usually contains residual strain generated during film growth. Strain control by improved deposition technique and implementing thermal treatment as well as choosing suitable substrate has attracted intensive attentions in ferroelectric film fabrication. Theory predicts that high dielectric properties can be achieved when free strain or slightly tensile strain left in the BST thin film at room temperature. Microwave application, such as phase shifter, also expects the enhanced tunability by an applied electric field. In this dissertation, single crystalline BST thin films deposited by radio frequency magnetron sputtering on SrTiO3 and DyScO3 substrates were studied. The crystal structure characteristics, including lattice parameters and film strain, were determined using X-ray diffraction. A new growth technique, three-step technique, was introduced and implemented into BST thin film deposition. The application of this new technique in deposition dramatically reduced the compressive strain in the films. We use microwave measurements on coplanar waveguides to evidence the improvement on dielectric properties achieved by tailoring the film strain. Additionally, we studied the BST film deposited by pulsed laser deposition (PLD) with introducing a sputtered seed layer of BST thin film. Compared with the BST film directly deposited on the substrate by PLD deposition, the films with a seed layer showed a large enhancement on the dielectric constant and tunability. The discussion on the change in film strain and dielectric performance of the PLD deposited films further proved the influence of film strain on dielectric properties. We discussed the design, fabrication, and measurement of coplanar waveguide transmission lines as phase shifters fabricated BST films. The thin BST films (~700 nm) on DyScO3 substrates deposited by sputtering demonstrated that the three-step deposition technique improved differential phase shift and microwave figure of merit to a great extent. The introduction of the sputtered seed layer into the PLD deposition of a thicker BST film (~2.15 [micro]m) showed a dramatically enhancement on differential phase shift and microwave figure of merit. The enhanced performance on different series of BST films in microwave frequencies is consistent with the improvement on crystal structure, especially with the change in film strain.

Book Growth  Characterization and Applications of Multifunctional Ferroelectric Thin Films

Download or read book Growth Characterization and Applications of Multifunctional Ferroelectric Thin Films written by Bo Xiao and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferroelectric materials have been extensively studied theoretically and experimentally for many decades. Their ferroelectric, piezoelectric, pyroelectric, dielectric and electro-optical properties offer great promise in various applications such as non-volatile random access memory devices, non linear optics, motion and thermal sensors, and tunable microwave devices. Advanced applications for high dielectric constant insulators and nonvolatile memories in semiconductor industry have led to a meteoric rise of interest in the ferroelectrics recently. As most studied and technically important ferroelectric materials, lead zirconate titanate (PZT) and barium strontium titanate (BST) are widely investigated to understand their properties for potential device applications. Using radio frequency magnetron sputtering, single crystalline PZT and BST thin films have been achieved on SrTiO3 substrates, and been characterized for their structural and electrical properties. Eyeing their different potential applications, ferroelectric, pyroelectric and dielectric properties of PZT and BST thin films were studied. In addition, the introduction of bridge layers (nucleation or buffer layers) grown by molecular beam epitaxy (MBE) has been employed to facilitate the heterostructure growth of PZT thin films on GaN and BST thin films on sapphire substrates. Highly (111)-oriented perovskite PZT thin films were achieved on silicon-doped GaN (0001)/c-sapphire with a PbTiO3/PbO oxide bridge layer. And (001)-oriented BST thin films were grown on a-plane sapphire with an MgO/ZnO bridge layer. This dissertation also discusses the realization of PZT ferroelectric field effect transistors (FeFET). Two different 1T FeFET structures were successfully fabricated and their electrical properties were examined. Ferroelectric behavior was observed in the plot of source-drain current versus gate voltage where it exhibited a large counterclockwise hysteresis with 50% current modulation.

Book Flexoelectricity of Barium Strontium Titanate and Its Applications

Download or read book Flexoelectricity of Barium Strontium Titanate and Its Applications written by Seol Ryung Kwon and published by . This book was released on 2014 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Frontiers of Ferroelectricity

Download or read book Frontiers of Ferroelectricity written by Sidney B. Lang and published by Springer Science & Business Media. This book was released on 2007-12-31 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents theory, fundamentals and applications of ferroelectricy. 24 chapters gather reviews and research reports covering the spectrum of ferroelectricity. It describes the current levels of understanding of various aspects of ferroelectricity as presented by authorities in the field. Topics include relaxors, piezoelectrics, microscale and nanoscale studies, polymers and composites, unusual properties, and techniques and devices. The book is intended for physicists, engineers and materials scientists working with ferroelectric materials.

Book Tuneable Film Bulk Acoustic Wave Resonators

Download or read book Tuneable Film Bulk Acoustic Wave Resonators written by Spartak Gevorgian and published by Springer Science & Business Media. This book was released on 2013-02-01 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: To handle many standards and ever increasing bandwidth requirements, large number of filters and switches are used in transceivers of modern wireless communications systems. It makes the cost, performance, form factor, and power consumption of these systems, including cellular phones, critical issues. At present, the fixed frequency filter banks based on Film Bulk Acoustic Resonators (FBAR) are regarded as one of the most promising technologies to address performance -form factor-cost issues. Even though the FBARs improve the overall performances the complexity of these systems remains high.a Attempts are being made to exclude some of the filters by bringing the digital signal processing (including channel selection) as close to the antennas as possible. However handling the increased interference levels is unrealistic for low-cost battery operated radios. Replacing fixed frequency filter banks by one tuneable filter is the most desired and widely considered scenario. As an example, development of the software based cognitive radios is largely hindered by the lack of adequate agile components, first of all tuneable filters. In this sense the electrically switchable and tuneable FBARs are the most promising components to address the complex cost-performance issues in agile microwave transceivers, smart wireless sensor networks etc.Tuneable Film Bulk Acoustic Wave Resonators discusses FBAR need, physics, designs, modelling, fabrication and applications. Tuning of the resonant frequency of the FBARs is considered. Switchable and tuneable FBARs based on electric field induced piezoelectric effect in paraelectric phase ferroelectrics are covered. The resonance of these resonators may be electrically switched on and off and tuned without hysteresis.The book is aimed at microwave and sensor specialists in the industry and graduate students. Readers will learn about principles of operation and possibilities of the switchable and tuneable FBARs, and will be given general guidelines for designing, fabrication and applications of these devices."

Book Properties of Materials

    Book Details:
  • Author : Robert E. Newnham
  • Publisher : Oxford University Press
  • Release : 2005
  • ISBN : 0198520751
  • Pages : 391 pages

Download or read book Properties of Materials written by Robert E. Newnham and published by Oxford University Press. This book was released on 2005 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crystals are sometimes called 'Flowers of the Mineral Kingdom'. In addition to their great beauty, crystals and other textured materials are enormously useful in electronics, optics, acoustics and many other engineering applications. This richly illustrated text describes the underlying principles of crystal physics and chemistry, covering a wide range of topics and illustrating numerous applications in many fields of engineering using the most important materials today. Tensors, matrices, symmetry and structure-property relationships form the main subjects of the book. While tensors and matrices provide the mathematical framework for understanding anisotropy, on which the physical and chemical properties of crystals and textured materials often depend, atomistic arguments are also needed to quantify the property coefficients in various directions. The atomistic arguments are partly based on symmetry and partly on the basic physics and chemistry of materials. After introducing the point groups appropriate for single crystals, textured materials and ordered magnetic structures, the directional properties of many different materials are described: linear and nonlinear elasticity, piezoelectricity and electrostriction, magnetic phenomena, diffusion and other transport properties, and both primary and secondary ferroic behavior. With crystal optics (its roots in classical mineralogy) having become an important component of the information age, nonlinear optics is described along with the piexo-optics, magneto-optics, and analogous linear and nonlinear acoustic wave phenomena. Enantiomorphism, optical activity, and chemical anisotropy are discussed in the final chapters of the book.

Book Nanostructured Metal Oxides and Devices

Download or read book Nanostructured Metal Oxides and Devices written by M. K. Jayaraj and published by Springer Nature. This book was released on 2020-04-16 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book primarily covers the fundamental science, synthesis, characterization, optoelectronic properties, and applications of metal oxide nanomaterials. It discusses the basic aspects of synthetic procedures and fabrication technologies, explains the related experimental techniques and also elaborates on the current status of nanostructured oxide materials and related devices. Two major aspects of metal oxide nanostructures – their optical and electrical properties – are described in detail. The first five chapters focus on the optical characteristics of semiconducting materials, especially metal oxides at the nanoscale. The following five chapters discuss the electrical properties observed in metal oxide-based semiconductors and the status quo of device-level developments in a variety of applications such as sensors, transistors, dilute magnetic semiconductors, and dielectric materials. The basic science and mechanism behind the optoelectronic phenomena are explained in detail, to aid readers interested in the structure–property symbiosis in semiconducting nanomaterials. In short, the book offers a valuable reference guide for researchers and academics in the areas of material science and semiconductor technology, especially nanophotonics and electronics.

Book Nanoscale Characterisation of Ferroelectric Materials

Download or read book Nanoscale Characterisation of Ferroelectric Materials written by Marin Alexe and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent advances in the field of nanoscale characterization of ferroelectric materials using scanning probe microscopy (SPM). It addresses various imaging mechanisms of ferroelectric domains in SPM, quantitative analysis of the piezoresponse signals as well as basic physics of ferroelectrics at the nanoscale level, such as nanoscale switching, scaling effects, and transport behavior. This state-of-the-art review of theory and experiments on nanoscale polarization phenomena will be a useful reference for advanced readers as well for newcomers and graduate students interested in the SPM techniques. The non-specialists will obtain valuable information about different approaches to electrical characterization by SPM, while researchers in the ferroelectric field will be provided with details of SPM-based measurements of ferroelectrics.

Book Piezoelectric Nanomaterials for Biomedical Applications

Download or read book Piezoelectric Nanomaterials for Biomedical Applications written by Gianni Ciofani and published by Springer Science & Business Media. This book was released on 2012-03-31 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoscale structures and materials have been explored in many biological applications because of their novel and impressive physical and chemical properties. Such properties allow remarkable opportunities to study and interact with complex biological processes. This book analyses the state of the art of piezoelectric nanomaterials and introduces their applications in the biomedical field. Despite their impressive potentials, piezoelectric materials have not yet received significant attention for bio-applications. This book shows that the exploitation of piezoelectric nanoparticles in nanomedicine is possible and realistic, and their impressive physical properties can be useful for several applications, ranging from sensors and transducers for the detection of biomolecules to “sensible” substrates for tissue engineering or cell stimulation.

Book Oxide Electronics

Download or read book Oxide Electronics written by Asim K. Ray and published by John Wiley & Sons. This book was released on 2021-04-12 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oxide Electronics Multiple disciplines converge in this insightful exploration of complex metal oxides and their functions and properties Oxide Electronics delivers a broad and comprehensive exploration of complex metal oxides designed to meet the multidisciplinary needs of electrical and electronic engineers, physicists, and material scientists. The distinguished author eschews complex mathematics whenever possible and focuses on the physical and functional properties of metal oxides in each chapter. Each of the sixteen chapters featured within the book begins with an abstract and an introduction to the topic, clear explanations are presented with graphical illustrations and relevant equations throughout the book. Numerous supporting references are included, and each chapter is self-contained, making them perfect for use both as a reference and as study material. Readers will learn how and why the field of oxide electronics is a key area of research and exploitation in materials science, electrical engineering, and semiconductor physics. The book encompasses every application area where the functional and electronic properties of various genres of oxides are exploited. Readers will also learn from topics like: Thorough discussions of High-k gate oxide for silicon heterostructure MOSFET devices and semiconductor-dielectric interfaces An exploration of printable high-mobility transparent amorphous oxide semiconductors Treatments of graphene oxide electronics, magnetic oxides, ferroelectric oxides, and materials for spin electronics Examinations of the calcium aluminate binary compound, perovoksites for photovoltaics, and oxide 2Degs Analyses of various applications for oxide electronics, including data storage, microprocessors, biomedical devices, LCDs, photovoltaic cells, TFTs, and sensors Suitable for researchers in semiconductor technology or working in materials science, electrical engineering, and physics, Oxide Electronics will also earn a place in the libraries of private industry researchers like device engineers working on electronic applications of oxide electronics. Engineers working on photovoltaics, sensors, or consumer electronics will also benefit from this book.

Book Polycrystalline And Amorphous Thin Films And Devices

Download or read book Polycrystalline And Amorphous Thin Films And Devices written by Lawrence Kazmerski and published by Elsevier. This book was released on 2012-12-02 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycrystalline and Amorphous Thin Films and Devices is a compilation of papers that discusses the electronic, optical, and physical properties of thin material layers and films. This compilation reviews the different applications of thin films of various materials used as protective and optical coatings, thermal transfer layers, and selective membranes from submicron- area VLSI memory units to large-area energy conservation devices. Some papers discuss the basic properties, such as growth, structure, electrical, and optical mechanisms that are encountered in amorphous and polycrystalline thin semiconductor films. For example, experiments on electronic structure of dislocations have led to a model for the intrinsic properties of grain boundaries in polycrystalline semiconductor thin films that can have an impact on the designs of high-efficiency, thin-film solar cells. Other papers review the problems encountered in these thin layers in active semiconductor devices and passive technologies. Techniques in film growth and control variables of source, substrate temperature, and substrate properties will determine the successful performance of the devices installed with these thin film layers. This compilation can prove valuable for chemists, materials engineers, industrial technologists, and researchers in thin-film technology.

Book Ferroelectricity in Doped Hafnium Oxide

Download or read book Ferroelectricity in Doped Hafnium Oxide written by Uwe Schroeder and published by Woodhead Publishing. This book was released on 2019-03-27 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferroelectricity in Doped Hafnium Oxide: Materials, Properties and Devices covers all aspects relating to the structural and electrical properties of HfO2 and its implementation into semiconductor devices, including a comparison to standard ferroelectric materials. The ferroelectric and field-induced ferroelectric properties of HfO2-based films are considered promising for various applications, including non-volatile memories, negative capacitance field-effect-transistors, energy storage, harvesting, and solid-state cooling. Fundamentals of ferroelectric and piezoelectric properties, HfO2 processes, and the impact of dopants on ferroelectric properties are also extensively discussed in the book, along with phase transition, switching kinetics, epitaxial growth, thickness scaling, and more. Additional chapters consider the modeling of ferroelectric phase transformation, structural characterization, and the differences and similarities between HFO2 and standard ferroelectric materials. Finally, HfO2 based devices are summarized. - Explores all aspects of the structural and electrical properties of HfO2, including processes, modelling and implementation into semiconductor devices - Considers potential applications including FeCaps, FeFETs, NCFETs, FTJs and more - Provides comparison of an emerging ferroelectric material to conventional ferroelectric materials with insights to the problems of downscaling that conventional ferroelectrics face

Book Ferroelectric Domain Walls

    Book Details:
  • Author : Jill Guyonnet
  • Publisher : Springer Science & Business Media
  • Release : 2014-04-08
  • ISBN : 3319057502
  • Pages : 167 pages

Download or read book Ferroelectric Domain Walls written by Jill Guyonnet and published by Springer Science & Business Media. This book was released on 2014-04-08 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using the nano metric resolution of atomic force microscopy techniques, this work explores the rich fundamental physics and novel functionalities of domain walls in ferroelectric materials, the nano scale interfaces separating regions of differently oriented spontaneous polarization. Due to the local symmetry-breaking caused by the change in polarization, domain walls are found to possess an unexpected lateral piezoelectric response, even when this is symmetry-forbidden in the parent material. This has interesting potential applications in electromechanical devices based on ferroelectric domain patterning. Moreover, electrical conduction is shown to arise at domain walls in otherwise insulating lead zirconate titanate, the first such observation outside of multiferroic bismuth ferrite, due to the tendency of the walls to localize defects. The role of defects is then explored in the theoretical framework of disordered elastic interfaces possessing a characteristic roughness scaling and complex dynamic response. It is shown that the heterogeneous disorder landscape in ferroelectric thin films leads to a breakdown of the usual self-affine roughness, possibly related to strong pinning at individual defects. Finally, the roles of varying environmental conditions and defect densities in domain switching are explored and shown to be adequately modelled as a competition between screening effects and pinning.

Book Lead Free Piezoelectric Materials

Download or read book Lead Free Piezoelectric Materials written by Jing-Feng Li and published by John Wiley & Sons. This book was released on 2021-07-06 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides in-depth knowledge on lead-free piezoelectrics - for state-of-the-art, environmentally friendly electrical and electronic devices! Lead zirconate titanate ceramics have been market-dominating due to their excellent properties and flexibility in terms of compositional modifications. Driven by the Restriction of Hazardous Substances Directive, there is a growing concern on the toxicity of lead. Therefore, numerous research efforts were devoted to lead-free piezoelectrics from the beginning of this century. Great progress has been made in the development of high-performance lead-free piezoelectric ceramics which are already used, e.g., for power electronics applications. Lead-Free Piezoelectric Materials provides an in-depth overview of principles, material systems, and applications of lead-free piezoelectric materials. It starts with the fundamentals of piezoelectricity and lead-free piezoelectrics. Then it discusses four representative lead-free piezoelectric material systems from background introduction to crystal structures and properties. Finally, it presents several applications of lead-free piezoelectrics including piezoelectric actuators, and transducers. The challenges for promoting applications will also be discussed. Highly attractive: Lead-free piezoelectrics address the growing concerns on exclusion of hazardous substances used in electrical and electronic devices in order to protect human health and the environment Thorough overview: Covers fundamentals, different classes of materials, processing and applications Unique: discusses fundamentals and recent advancements in the field of lead-free piezoelectrics Lead-Free Piezoelectric Materials is of high interest for material scientists, electrical and chemical engineers, solid state chemists and physicists in academia and industry.