Magnetic and ferroelectric properties of oxygen octahedron/tetrahedron mixed ultrathin multiferroic layer by oxygen desorption

2021 ◽  
Vol 129 (3) ◽  
pp. 034101
Author(s):  
T. Ichinose ◽  
H. Naganuma
Keyword(s):  
Ferroelectric Properties ◽  
Oxygen Desorption ◽  
Oxygen Octahedron

Quantitative surface damage studies by H.R.E.M.

1989 ◽  
Vol 47 ◽  
pp. 632-633
Author(s):  
S. R. Singh ◽  
H. J. Fan ◽  
L. D. Marks
Keyword(s):  
Solar Wind ◽  
Quantitative Analysis ◽  
Surface Science ◽  
Surface Damage ◽  
Space Environment ◽  
Oxygen Desorption ◽  
The Past ◽  
Diffusion Controlled ◽  
Original Observation ◽  
Substantial Interest

Since the original observation that the surfaces of materials undergo radiation damage in the electron microscope similar to that observed by more conventional surface science techniques there has been substantial interest in understanding these phenomena in more detail; for a review see. For instance, surface damage in a microscope mimics damage in the space environment due to the solar wind and electron beam lithographic operations.However, purely qualitative experiments that have been done in the past are inadequate. In addition, many experiments performed in conventional microscopes may be inaccurate. What is needed is careful quantitative analysis including comparisons of the behavior in UHV versus that in a conventional microscope. In this paper we will present results of quantitative analysis which clearly demonstrate that the phenomena of importance are diffusion controlled; more detailed presentations of the data have been published elsewhere.As an illustration of the results, Figure 1 shows a plot of the shrinkage of a single, roughly spherical particle of WO3 versus time (dose) driven by oxygen desorption from the surface.

Epitaxial ferroelectric thin films

1994 ◽  
Vol 52 ◽  
pp. 572-573
Author(s):  
S. G. Ghonge ◽  
E. Goo ◽  
R. Ramesh ◽  
R. Haakenaasen ◽  
D. K. Fork
Keyword(s):  
Single Crystal ◽  
Work Function ◽  
Nonvolatile Memory ◽  
Ferroelectric Properties ◽  
Electrical Contact ◽  
Memory Devices ◽  
Ferroelectric Films ◽  
Si Substrates ◽  
Electro Optic ◽  
Wide Range

Microstructure of epitaxial ferroelectric/conductive oxide heterostructures on LaAIO3(LAO) and Si substrates have been studied by conventional and high resolution transmission electron microscopy. The epitaxial films have a wide range of potential applications in areas such as non-volatile memory devices, electro-optic devices and pyroelectric detectors. For applications such as electro-optic devices the films must be single crystal and for applications such as nonvolatile memory devices and pyroelectric devices single crystal films will enhance the performance of the devices. The ferroelectric films studied are Pb(Zr0.2Ti0.8)O3(PLZT), PbTiO3(PT), BiTiO3(BT) and Pb0.9La0.1(Zr0.2Ti0.8)0.975O3(PLZT).Electrical contact to ferroelectric films is commonly made with metals such as Pt. Metals generally have a large difference in work function compared to the work function of the ferroelectric oxides. This results in a Schottky barrier at the interface and the interfacial space charge is believed to responsible for domain pinning and degradation in the ferroelectric properties resulting in phenomenon such as fatigue.

Effects of LaFeO3 Additions on the Dielectric and Ferroelectric Properties of (K0.5Na0.5)NbO3 Ceramics

2013 ◽  
Vol 27 (11) ◽  
pp. 1228-1232 ◽  
Author(s):  
Hua-Lei CHENG ◽  
Hong-Liang DU ◽  
Wan-Cheng ZHOU ◽  
Fa LUO ◽  
Dong-Mei ZHU
Keyword(s):  
Ferroelectric Properties

An Investigation of the Conductive and Ferroelectric Properties of BZT Films

2020 ◽  
Vol 65 (12) ◽  
pp. 2066-2071
Author(s):  
E. V. Gushchina ◽  
B. R. Borodin ◽  
V. A. Sharov ◽  
V. V. Osipov ◽  
S. I. Pavlov ◽  
...  
Keyword(s):  
Ferroelectric Properties

scholarly journals Composite Ferroelectric Membranes Based on Vinylidene Fluoride-Tetrafluoroethylene Copolymer and Polyvinylpyrrolidone for Wound Healing

Membranes ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 21
Author(s):  
Tamara S. Tverdokhlebova ◽  
Ludmila S. Antipina ◽  
Valeriya L. Kudryavtseva ◽  
Ksenia S. Stankevich ◽  
Ilya M. Kolesnik ◽  
...  
Keyword(s):  
Wound Healing ◽  
Vinylidene Fluoride ◽  
Ferroelectric Properties ◽  
Composite Membranes ◽  
Modern Medicine ◽  
In Vivo Studies ◽  
Cytotoxic Effects ◽  
Complex Process ◽  
Purulent Wounds

Wound healing is a complex process and an ongoing challenge for modern medicine. Herein, we present the results of study of structure and properties of ferroelectric composite polymer membranes for wound healing. Membranes were fabricated by electrospinning from a solution of vinylidene fluoride/tetrafluoroethylene copolymer (VDF–TeFE) and polyvinylpyrrolidone (PVP) in dimethylformamide (DMF). The effects of the PVP content on the viscosity and conductivity of the spinning solution, DMF concentration, chemical composition, crystal structure, and conformation of VDF–TeFE macromolecules in the fabricated materials were studied. It was found that as PVP amount increased, the viscosity and conductivity of the spinning solutions decreased, resulting in thinner fibers. Using FTIR and XRD methods, it was shown that if the PVP content was lower than 50 wt %, the VDF–TeFE copolymer adopted a flat zigzag conformation (TTT conformation) and crystalline phases with ferroelectric properties were formed. Gas chromatography results indicated that an increase in the PVP concentration led to a higher residual amount of DMF in the material, causing cytotoxic effects on 3T3L1 fibroblasts. In vivo studies demonstrated that compared to classical gauze dressings impregnated with a solution of an antibacterial agent, ferroelectric composite membranes with 15 wt % PVP provided better conditions for the healing of purulent wounds.

Impact of area scaling on the ferroelectric properties of back-end of line compatible Hf0.5Zr0.5O2 and Si:HfO2-based MFM capacitors

2021 ◽  
Vol 118 (6) ◽  
pp. 062904
Author(s):  
T. Francois ◽  
L. Grenouillet ◽  
J. Coignus ◽  
N. Vaxelaire ◽  
C. Carabasse ◽  
...  
Keyword(s):  
Ferroelectric Properties

scholarly journals Boron Influence on Defect Structure and Properties of Lithium Niobate Crystals

Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 458
Author(s):  
Nikolay V. Sidorov ◽  
Natalia A. Teplyakova ◽  
Olga V. Makarova ◽  
Mikhail N. Palatnikov ◽  
Roman A. Titov ◽  
...  
Keyword(s):  
Lithium Niobate ◽  
Defect Structure ◽  
Photorefractive Effect ◽  
Ferroelectric Properties ◽  
High Concentration ◽  
Oh Groups ◽  
Boron Doped ◽  
Compositional Uniformity ◽  
Boron Dopant ◽  
Lithium Niobate Crystals

Defect structure of nominally pure lithium niobate crystals grown from a boron doped charge have been studied by Raman and optical spectroscopy, laser conoscopy, and photoinduced light scattering. An influence of boron dopant on optical uniformity, photoelectrical fields values, and band gap have been also studied by these methods in LiNbO3 crystals. Despite a high concentration of boron in the charge (up to 2 mol%), content in the crystal does not exceed 10−4 wt%. We have calculated that boron incorporates only into tetrahedral voids of crystal structure as a part of groups [BO3]3−, which changes O–O bonds lengths in O6 octahedra. At this oxygen–metal clusters MeO6 (Me: Li, Nb) change their polarizability. The clusters determine optically nonlinear and ferroelectric properties of a crystal. Chemical interactions in the system Li2O–Nb2O5–B2O3 have been considered. Boron, being an active element, structures lithium niobate melt, which significantly influences defect structure and physical properties of a crystal grown from such a melt. At the same time, amount of defects NbLi and concentration of OH groups in LiNbO3:B is close to that in stoichiometric crystals; photorefractive effect, optical, and compositional uniformity on the contrary is higher.

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