The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Ya Yang - One of the best experts on this subject based on the ideXlab platform.
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enhanced photocurrent via ferro pyro phototronic effect in Ferroelectric batio3 Materials for a self powered flexible photodetector system
Nano Energy, 2020Co-Authors: Kun Zhao, Ya Yang, Bangsen Ouyang, C R BowenAbstract:Abstract Some Ferroelectric Materials have demonstrated both pyroelectric and photovoltaic effects for scavenging thermal and solar energies. However, how to couple pyroelectric and photovoltaic effects in Ferroelectric Materials remains a challenge. Here, a ferro-pyro-phototronic effect based on coupling pyroelectric and photovoltaic effects has been utilized to enhance the photocurrent in a Ferroelectric BaTiO3-based flexible photodetector system. As compared with a purely photovoltaic system, the corresponding current peak and plateau were 451.9% and 17.2% higher in the coupled photovoltaic-pyroelectric system, respectively. The results can be explained by ferro-pyro-phototronic effect with an induced energy band bending. As a demonstration of its potential application, we developed a sensing system that is suitable for detecting and recognizing both light and temperature variations by recording the electrical signals mapped as an array.
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effective polarization of Ferroelectric Materials by using a triboelectric nanogenerator to scavenge wind energy
Nano Energy, 2018Co-Authors: Xi Liu, Kun Zhao, Ya YangAbstract:Abstract Effective polarization of Ferroelectric Materials can be achieved by utilizing a conventional high-voltage polarization equipment with a high voltage but a large volume. Here, we report that the polarization of a Ferroelectric BaTiO3 material can be realized by using a triboelectric nanogenerator (TENG) to scavenge ambient wind energy, where the TENG is ideal for providing a higher voltage, a smaller current, and especially a smaller volume. Both the output voltage and current signals of TENG can be adjustable by controlling different wind speeds, where the TENG can deliver an output voltage pulse (
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Boosted photocurrent in Ferroelectric BaTiO3 Materials via two dimensional planar-structured contact configurations
Nano Energy, 2018Co-Authors: Ya YangAbstract:Abstract Photocurrent can be generated in Ferroelectric devices with vertical-structured sandwich configurations due to photovoltaic effect, which has potential applications in electronic devices such as photodetectors owing to no use of any external power source. However, how to effectively enhance the photocurrent in Ferroelectric Materials still remains one of the key challenges for these applications. We report a dramatic increase of photocurrent in a Ferroelectric BaTiO3-based self-powered photodetector by utilizing two dimensional planar-structured contact electrode configurations. As compared with that of conventional vertical-structured device, the fabricated planar-structured device exhibits over 900-fold enhancement of stable photocurrent under 365 nm UV light illumination. A physical model based on band energy theory has been utilized to explain the origin of the observed phenomenon. The remarkable enhancement of photocurrent in Ferroelectric Materials by using this route will open a new area of two dimensional planar-structured Ferroelectric photodetectors.
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photovoltaic pyroelectric coupled effect induced electricity for self powered photodetector system
Advanced Materials, 2017Co-Authors: Ya Yang, Kewei ZhangAbstract:Ferroelectric Materials have demonstrated novel photovoltaic effect to scavenge solar energy. However, most of the Ferroelectric Materials with wide bandgaps (2.7–4 eV) suffer from low power conversion efficiency of less than 0.5% due to absorbing only 8–20% of solar spectrum. Instead of harvesting solar energy, these Ferroelectric Materials can be well suited for photodetector applications, especially for sensing near-UV irradiations. Here, a Ferroelectric BaTiO3 film-based photodetector is demonstrated that can be operated without using any external power source and a fast sensing of 405 nm light illumination is enabled. As compared with photovoltaic effect, both the responsivity and the specific detectivity of the photodetector can be dramatically enhanced by larger than 260% due to the light-induced photovoltaic–pyroelectric coupled effect. A self-powered photodetector array system can be utilized to achieve spatially resolved light intensity detection by recording the output voltage signals as a mapping figure.
Ralph C Smith - One of the best experts on this subject based on the ideXlab platform.
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the homogenized energy model hem for characterizing polarization and strains in hysteretic Ferroelectric Materials material properties and uniaxial model development
Journal of Intelligent Material Systems and Structures, 2012Co-Authors: Ralph C Smith, Zhengzheng HuAbstract:Ferroelectric Materials, such as lead zirconate titanate, lanthanum-doped lead zirconate titanate, and BaTiO3, are being considered, or are already being employed, for a large number of applications including nanopositioning, high-speed valves for fuel injectors, ultrasonic transducers, high-speed camera shutters and autofocusing mechanisms, energy harvesting, and pico air vehicle design. Their advantages include nanometer positioning resolution, broadband frequency responses, moderate power requirements, the capability for miniaturization, and complementary actuator and sensor capabilities. However, they also exhibit creep, rate-dependent hysteresis, and constitutive nonlinearities at essentially all drive levels due to their noncentrosymmetric nature. In this article, we model the hysteretic dependence of strains and polarizations on input fields and stresses using the homogenized energy model framework. At the domain level, the minimization of the Gibbs energy densities yields linear constitutive relat...
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the homogenized energy model hem for characterizing polarization and strains in hysteretic Ferroelectric Materials material properties and uniaxial model development
Journal of Intelligent Material Systems and Structures, 2012Co-Authors: Ralph C SmithAbstract:Ferroelectric Materials, such as lead zirconate titanate, lanthanum-doped lead zirconate titanate, and BaTiO3, are being considered, or are already being employed, for a large number of application...
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a stress dependent hysteresis model for Ferroelectric Materials
Journal of Intelligent Material Systems and Structures, 2007Co-Authors: Brian Lee Ball, Ralph C Smith, Sangjoo Kim, Stefan SeeleckeAbstract:This article addresses the development of a homogenized energy model which characterizes the ferroelastic switching mechanisms inherent to Ferroelectric Materials in a manner suitable for subsequent transducer and control design. In the first step of the development, we construct Helmholtz and Gibbs energy relations which quantify the potential and electrostatic energy associated with 90 and 180 dipole orientations. Equilibrium relations appropriate for homogeneous Materials in the absence or presence of thermal relaxation are respectively determined by minimizing the Gibbs energy or balancing the Gibbs and relative thermal energies using Boltzmann principles. In the final step of the development, stochastic homogenization techniques are employed to construct macroscopic models suitable for nonhomogeneous, polycrystalline compounds. Attributes and limitations of the characterization framework are illustrated through comparison with experimental PLZT data.
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a free energy model for hysteresis in Ferroelectric Materials
Journal of Intelligent Material Systems and Structures, 2003Co-Authors: Ralph C Smith, Stefan Seelecke, Zoubeida Ounaies, Joshua Ryan SmithAbstract:This paper provides a theory for quantifying the hysteresis and constitutive nonlinearities inherent to piezoceramic compounds through a combination of free energy analysis and stochastic homogenization techniques. In the first step of the model development, Helmholtz and Gibbs free energy relations are constructed at the lattice or domain level to quantify the relation between the field and polarization in homogeneous, single crystal compounds which exhibit uniform effective fields. The effects of material nonhomogeneities, polycrystallinity, and variable effective fields are subsequently incorporated through the assumption that certain physical parameters, including the local coercive and effective fields, are randomly distributed and hence manifestations of stochastic density functions associated with the material. Stochastic homogenization in this manner provides low-order macroscopic models with effective parameters that can be correlated with physical properties of the data. This facilitates the ide...
Sergei V Kalinin - One of the best experts on this subject based on the ideXlab platform.
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local polarization dynamics in Ferroelectric Materials
ChemInform, 2011Co-Authors: Sergei V Kalinin, Anna N Morozovska, Long Qing Chen, Brian J RodriguezAbstract:Ferroelectrics and multiferroics have recently emerged as perspective Materials for information technology and data storage applications. The combination of extremely narrow domain wall width and the capability to manipulate polarization by electric field opens the pathway toward ultrahigh (>10 TBit inch−2) storage densities and small (sub-10 nm) feature sizes. The coupling between polarization and chemical and transport properties enables applications in Ferroelectric lithography and electroresistive devices. The progress in these applications, as well as fundamental studies of polarization dynamics and the role of defects and disorder on domain nucleation and wall motion, requires the capability to probe these effects on the nanometer scale. In this review, we summarize the recent progress in applications of piezoresponse force microscopy (PFM) for imaging, manipulation and spectroscopy of Ferroelectric switching processes. We briefly introduce the principles and relevant instrumental aspects of PFM, with special emphasis on resolution and information limits. The local imaging studies of domain dynamics, including local switching and relaxation accessed through imaging experiments and spectroscopic studies of polarization switching, are discussed in detail. Finally, we review the recent progress on understanding and exploiting photochemical processes on Ferroelectric surfaces, the role of surface adsorbates, and imaging and switching in liquids. Beyond classical applications, probing local bias-induced transition dynamics by PFM opens the pathway to studies of the influence of a single defect on electrochemical and solid state processes, thus providing model systems for batteries, fuel cells and supercapacitor applications.
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high resolution electromechanical imaging of Ferroelectric Materials in a liquid environment by piezoresponse force microscopy
Physical Review Letters, 2006Co-Authors: Brian J Rodriguez, Stephen Jesse, Arthur P Baddorf, Sergei V KalininAbstract:High-resolution imaging of Ferroelectric Materials using piezoresponse force microscopy (PFM) is demonstrated in an aqueous environment. The elimination of both long-range electrostatic forces and capillary interactions results in a localization of the ac field to the tip-surface junction and allows the tip-surface contact area to be controlled. This approach results in spatial resolutions approaching the limit of the intrinsic domain-wall width. Imaging at frequencies corresponding to high-order cantilever resonances minimizes the viscous damping and added mass effects on cantilever dynamics and allows sensitivities comparable to ambient conditions. PFM in liquids will provide novel opportunities for high-resolution studies of Ferroelectric Materials, imaging of soft polymer Materials, and imaging of biological systems in physiological environments on, ultimately, the molecular level.
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spatial resolution information limit and contrast transfer in piezoresponse force microscopy
Nanotechnology, 2006Co-Authors: Sergei V Kalinin, Stephen Jesse, Arthur P Baddorf, Brian J Rodriguez, Junsoo Shin, Ho Nyung Lee, Albina Y Borisevich, Stephen J PennycookAbstract:Scanning probe-based Ferroelectric domain imaging and patterning has attracted broad attention for use in the characterization of Ferroelectric Materials, ultrahigh density data storage, and nanofabrication. The viability of these applications is limited by the minimal domain size that can be fabricated and reliably detected by scanning probe microscopy. Here, the contrast transfer mechanism in piezoresponse force microscopy (PFM) of Ferroelectric Materials is analysed in detail. A consistent definition of resolution is developed both for the writing and the imaging processes, and the concept of an information limit in PFM is established. Experimental determination of the object transfer function and the subsequent reconstruction of an 'ideal image' is demonstrated. This contrast transfer theory provides a quantitative basis for image interpretation and allows for the comparison of different instruments in PFM. It is shown that experimentally observed domain sizes can be limited by the resolution of the scanning probe microscope to the order of tens of nanometres even though smaller domains, of the order of several nanometres, can be created.
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switching spectroscopy piezoresponse force microscopy of Ferroelectric Materials
Applied Physics Letters, 2006Co-Authors: Stephen Jesse, Arthur P Baddorf, Sergei V KalininAbstract:The application of Ferroelectric Materials for electronic devices necessitates the quantitative study of local switching behavior, including imprint, coercive bias, remanent and saturation responses, and work of switching. Here we introduce switching spectroscopy piezoresponse force microscopy as a tool for real-space imaging of switching properties on the nanoscale. The hysteresis curves, acquired at each point in the image, are analyzed in the thermodynamic and kinetic limits. We expect that this approach will further understanding of the relationships between material microstructure and polarization switching phenomena on the nanoscale, and provide a quantitative tool for Ferroelectric-based device characterization.
Yoshinori Tokura - One of the best experts on this subject based on the ideXlab platform.
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hydrogen bonded donor acceptor compounds for organic Ferroelectric Materials
Chemical Communications, 2007Co-Authors: Sachio Horiuchi, Reiji Kumai, Yoshinori TokuraAbstract:Organic Ferroelectrics are multifunctional candidates for future organic electronic and optical devices. In spite of their potential, only a few organic compounds are known to exhibit a Ferroelectric transition. The conventional approach to Ferroelectrics, in general, relies on the use of asymmetric dipolar molecules and/or substituents. Recently, distinct design strategies have been developed using the molecular compounds of binary- or multi-components, combined with “non-covalent” forces: charge-transfer interactions and/or hydrogen bonding. This article focuses on the supramolecular systems of hydrogen-bonded acid and base molecules. Ferroelectricity and a significant dielectric response, as well as an antiFerroelectric ordering induced by proton transfer, are demonstrated in the hydrogen-bonded chains composed of 2,5-dihydroxy-p-benzoquinone derivatives and nitrogen-containing aromatic bases.
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Ferroelectricity near room temperature in co crystals of nonpolar organic molecules
Nature Materials, 2005Co-Authors: Sachio Horiuchi, Fumiyuki Ishii, Reiji Kumai, Y Okimoto, Hiroaki Tachibana, Naoto Nagaosa, Yoshinori TokuraAbstract:The research on Ferroelectric Materials—mostly inorganic compounds or organic polymers1,2,3—is increasingly motivated by both basic scientific concerns and the potential for practical applications in electronics and optics. Ferroelectricity in organic solids would be important for the development of all-organic electronic and photonic devices. The conventional approach to making organic Ferroelectrics is based on the use of polar molecules. Here we report that through supramolecular assembly of nonpolar conjugated molecules, a remarkable Ferroelectric response can be obtained in co-crystals of low-molecular-weight organic compounds. Co-crystals of phenazine and chloranilic acid reveal large spontaneous polarization and sizable room-temperature dielectric constants exceeding 100. The present findings provide an approach to making potentially useful organic Ferroelectric Materials.
Stephen Jesse - One of the best experts on this subject based on the ideXlab platform.
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high resolution electromechanical imaging of Ferroelectric Materials in a liquid environment by piezoresponse force microscopy
Physical Review Letters, 2006Co-Authors: Brian J Rodriguez, Stephen Jesse, Arthur P Baddorf, Sergei V KalininAbstract:High-resolution imaging of Ferroelectric Materials using piezoresponse force microscopy (PFM) is demonstrated in an aqueous environment. The elimination of both long-range electrostatic forces and capillary interactions results in a localization of the ac field to the tip-surface junction and allows the tip-surface contact area to be controlled. This approach results in spatial resolutions approaching the limit of the intrinsic domain-wall width. Imaging at frequencies corresponding to high-order cantilever resonances minimizes the viscous damping and added mass effects on cantilever dynamics and allows sensitivities comparable to ambient conditions. PFM in liquids will provide novel opportunities for high-resolution studies of Ferroelectric Materials, imaging of soft polymer Materials, and imaging of biological systems in physiological environments on, ultimately, the molecular level.
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spatial resolution information limit and contrast transfer in piezoresponse force microscopy
Nanotechnology, 2006Co-Authors: Sergei V Kalinin, Stephen Jesse, Arthur P Baddorf, Brian J Rodriguez, Junsoo Shin, Ho Nyung Lee, Albina Y Borisevich, Stephen J PennycookAbstract:Scanning probe-based Ferroelectric domain imaging and patterning has attracted broad attention for use in the characterization of Ferroelectric Materials, ultrahigh density data storage, and nanofabrication. The viability of these applications is limited by the minimal domain size that can be fabricated and reliably detected by scanning probe microscopy. Here, the contrast transfer mechanism in piezoresponse force microscopy (PFM) of Ferroelectric Materials is analysed in detail. A consistent definition of resolution is developed both for the writing and the imaging processes, and the concept of an information limit in PFM is established. Experimental determination of the object transfer function and the subsequent reconstruction of an 'ideal image' is demonstrated. This contrast transfer theory provides a quantitative basis for image interpretation and allows for the comparison of different instruments in PFM. It is shown that experimentally observed domain sizes can be limited by the resolution of the scanning probe microscope to the order of tens of nanometres even though smaller domains, of the order of several nanometres, can be created.
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switching spectroscopy piezoresponse force microscopy of Ferroelectric Materials
Applied Physics Letters, 2006Co-Authors: Stephen Jesse, Arthur P Baddorf, Sergei V KalininAbstract:The application of Ferroelectric Materials for electronic devices necessitates the quantitative study of local switching behavior, including imprint, coercive bias, remanent and saturation responses, and work of switching. Here we introduce switching spectroscopy piezoresponse force microscopy as a tool for real-space imaging of switching properties on the nanoscale. The hysteresis curves, acquired at each point in the image, are analyzed in the thermodynamic and kinetic limits. We expect that this approach will further understanding of the relationships between material microstructure and polarization switching phenomena on the nanoscale, and provide a quantitative tool for Ferroelectric-based device characterization.