scholarly journals Mobile and immobile boundaries in ferroelectric films

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. Yudin ◽  
K. Shapovalov ◽  
T. Sluka ◽  
J. Peräntie ◽  
H. Jantunen ◽  
...  
Keyword(s):  
Long Range ◽  
Domain Walls ◽  
Ferroelectric Properties ◽  
Practical Importance ◽  
Dynamic Responses ◽  
Ferroelectric Films ◽  
Domain Structures ◽  
Mobile Interfaces ◽  
Ferroelastic Domains ◽  
Viable Method

AbstractThe intrinsic mobile interfaces in ferroelectrics—the domain walls can drive and enhance diverse ferroelectric properties, essential for modern applications. Control over the motion of domain walls is of high practical importance. Here we analyse theoretically and show experimentally epitaxial ferroelectric films, where mobile domain walls coexist and interact with immobile growth-induced interfaces—columnar boundaries. Whereas these boundaries do not disturb the long-range crystal order, they affect the behaviour of domain walls in a peculiar selective manner. The columnar boundaries substantially modify the behaviour of non-ferroelastic domains walls, but have negligible impact on the ferroelastic ones. The results suggest that introduction of immobile boundaries into ferroelectric films is a viable method to modify domain structures and dynamic responses at nano-scale that may serve to functionalization of a broader range of ferroelectric films where columnar boundaries naturally appear as a result of the 3D growth.

scholarly journals Creating multiferroic and conductive domain walls in common ferroelastic compounds

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Hong Jian Zhao ◽  
Jorge Íñiguez
Keyword(s):  
Long Range ◽  
Functional Properties ◽  
First Principles ◽  
Domain Walls ◽  
Nano Materials ◽  
Ordered Structures ◽  
Clear Cut ◽  
Domain Structures ◽  
Wide Range ◽  
Recent Developments

Abstract Domain walls in ferroelectrics and ferroelastics often present peculiar functional properties, offering an intriguing route toward the design of nano-devices. Here we use first-principles simulations to illustrate an approach for engineering such walls, working with representative ferroelastic perovskites LaGaO3 and CaTiO3 (insulating, non-magnetic, non-polar). We show that a wide range of substitutional dopants can be used to create long-range-ordered structures confined within the walls of these compounds, yielding functional interfaces with tailor-made properties. We thus identify clear-cut strategies to produce metallic walls within an insulating matrix. Further, we find ways to create magnetic walls that also display ferroelectric order (proper or improper), thus providing an original route to obtain magnetoelectric multiferroics. Given the recent developments on the preparation of high-density domain structures in perovskite films, our results suggest a definite path toward new functional nano-materials.

Imaging of Ferroelectric Domains in KTiOPO4 Single Crystals by Synchrotron X-RAY Topography

1993 ◽  
Vol 310 ◽  
Author(s):  
S. Wang ◽  
M. Dudley ◽  
L.K. Cheng ◽  
J.D. Bierlein ◽  
W. Bindloss
Keyword(s):  
Domain Wall ◽  
Single Crystals ◽  
Long Range ◽  
Domain Walls ◽  
Three Dimensional ◽  
Dynamical Theory ◽  
X Ray Diffraction ◽  
X Ray ◽  
Domain Structures ◽  
Main Components

AbstractThe application of synchrotron white beam X-ray topography to the study of ferroelectric domain structures in hydrothermally grown potassium titanyl phosphate (KTiOPO4: KTP) single crystals is reported. The domain walls can be exclusively imaged on topographs with selected diffraction vectors and X-ray wavelengths, while images of other defects, such as dislocations, inclusions and surface scratches, can be simultaneously made very diffuse. The topographic images correspond well with electrostatic toning images. X-ray topography readily reveals the three dimensional shapes of the domain walls. There are two contributions to domain wall contrast: one is fringe-like which can be interpreted in terms of the dynamical theory of X-ray diffraction, and the other is diffuse strain contrast arising from long range strain associated with the wall. These two contributions can be observed simultaneously or separately depending on the diffraction conditions. The long range strain is thought to be associated with the curvature of the domain walls. It appears that the main components of the displacement field associated with this strain are directed approximately perpendicular to the domain wall.

Temperature Dependence of Magnetic Domains and Wall Structures

1972 ◽  
Vol 30 ◽  
pp. 496-497
Author(s):  
Sonoko Tsukahara ◽  
Tadami Taoka ◽  
Hisao Nishizawa
Keyword(s):  
Temperature Dependence ◽  
Domain Walls ◽  
Magnetic Domain ◽  
Iron Film ◽  
Objective Lens ◽  
Lorentz Microscopy ◽  
Domain Structures ◽  
Wall Structures ◽  
Crystal Films ◽  
Metallurgical Structure

The high voltage Lorentz microscopy was successfully used to observe changes with temperature; of domain structures and metallurgical structures in an iron film set on the hot stage combined with a goniometer. The microscope used was the JEM-1000 EM which was operated with the objective lens current cut off to eliminate the magnetic field in the specimen position. Single crystal films with an (001) plane were prepared by the epitaxial growth of evaporated iron on a cleaved (001) plane of a rocksalt substrate. They had a uniform thickness from 1000 to 7000 Å.The figure shows the temperature dependence of magnetic domain structure with its corresponding deflection pattern and metallurgical structure observed in a 4500 Å iron film. In general, with increase of temperature, the straight domain walls decrease in their width (at 400°C), curve in an iregular shape (600°C) and then vanish (790°C). The ripple structures with cross-tie walls are observed below the Curie temperature.

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.

Long-range strains and the effects of applied field at 180° ferroelectric domain walls in lithium niobate

2004 ◽  
Vol 69 (6) ◽  
Author(s):  
Terrence Jach ◽  
Sungwon Kim ◽  
Venkatraman Gopalan ◽  
Stephen Durbin ◽  
David Bright
Keyword(s):  
Lithium Niobate ◽  
Long Range ◽  
Applied Field ◽  
Domain Walls ◽  
Ferroelectric Domain

Deepening of domains at e-beam writing on the -Z surface of lithium niobate

2021 ◽  
Author(s):  
Lyudmila Kokhanchik ◽  
Evgenii Emelin ◽  
Vadim Vladimirovch Sirotkin ◽  
Alexander Svintsov
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Lithium Niobate ◽  
Electric Field ◽  
Domain Walls ◽  
Normal Component ◽  
Beam Current ◽  
Near Surface ◽  
Domain Structures ◽  
Sign Inversion

Abstract The focus of the study was to investigate the peculiarities of the domains created by electron beam (e-beam) in a surface layer of congruent lithium niobate, which comparable to a depth of electron beam charge penetration. Direct e-beam writing (DEBW) of different domain structures with a scanning electron microscope was performed on the polar -Z cut. Accelerating voltage 15 kV and e-beam current 100 pA were applied. Different patterns of local irradiated squares were used to create domain structures and single domains. No domain contrast was observed by the PFM technique. Based on chemical etching, it was found that the vertices of the domains created do not reach the surface level. The average deepening of the domain vertices was several hundred nanometers and varied depending on the irradiation dose and the location of the irradiated areas (squares) relative to each other. Computer simulation was applied to analyze the spatial distribution of the electric field in the various irradiated patterns. The deepening was explained by the fact that in the near-surface layer there is a sign inversion of the normal component of the electric field strength vector, which controls the domain formation during DEBW. Thus, with the help of e-beam, domains were created completely located in the bulk, in contrast to the domains that are nucleated on the surface of the -Z cut during the polarization inversion with AFM tip. The detected deepening of e-beam domains suggests the possibility of creating the “head-to-head” domain walls in the near-surface layer lithium niobate by DEBW.

Want Engaged Employees? Encourage Human Resource and Enhance Organizational Connectedness

2021 ◽  
Vol 6 (1) ◽  
pp. 1-12
Author(s):  
Abhishek Sharma
Keyword(s):  
Employee Engagement ◽  
Human Resource ◽  
Work Engagement ◽  
Organizational Identification ◽  
Practical Importance ◽  
Study Data ◽  
Organizational Productivity ◽  
Hr Practices ◽  
The Relationship ◽  
Viable Method

Work engagement is not only a "nice-to-have" but has been shown to be linked to various positive outcomes of work, including its proven financial and behavioural gains. The concern regarding employee engagement is increasing, and organizations of the 21st century are looking for every possible way to develop the culture of employee engagement deliberately. In this context, this research introduces employee engagement as a viable method to encourage organizational productivity and examines how perceptions of specific human resource (HR) practices and organizational identification relate to experiences of employee's work engagement. The study data was collected using standard psychometric tools from 75 mid-level managers working in various organizations. Statistical analysis was performed to answer research questions. The results conveyed the significance of applying encouraging human resource practices and demonstrated the positive effect of organization-al identification (OID) on work engagement. HR practices and OID were found instrumental in positively predicting the significant amount of work engagement. By discovering the relationship between HR practices (conditions that organizations can influence easily), organizational identification, and employee engagement, this study relates to the realistic implementation of measures to improve employee engagement and especially emphasises them. As most companies are searching for ways to promote employee engagement, the latest re-search results are of practical importance to HR executives.

Domain Walls Creep in Thin Ferroelectric Films

2015 ◽  
Vol 476 (1) ◽  
pp. 34-39 ◽  
Author(s):  
A. S. Sidorkin ◽  
L. P. Nesterenko ◽  
A. Yu. Pakhomov ◽  
B. M. Darinskii
Keyword(s):  
Domain Walls ◽  
Ferroelectric Films

scholarly journals Магнитостатическая энергия доменных стенок в одноосных пленках конечных размеров

2019 ◽  
Vol 61 (10) ◽  
pp. 1767
Author(s):  
П.М. Ветошко ◽  
Ф.П. Ветошко ◽  
В.Г. Шавров ◽  
В.И. Щеглов
Keyword(s):  
Domain Walls ◽  
Magnetic Sensors ◽  
Magnetization Distribution ◽  
Magnetic Memory ◽  
Spintronic Devices ◽  
Domain Structures ◽  
Magnetic Elements ◽  
Uniform Magnetization ◽  
Equilibrium Configurations ◽  
Equivalent Currents

AbstractThe solution to the problem of calculating the magnetostatic interaction energy of domain walls in uniaxial magnetics with a uniform magnetization distribution inside the domains is given. In carrying out the calculations, the principle of equivalent currents is used, assuming a uniform distribution of magnetization and its representation by equivalent currents flowing along the domain walls and along the surface. Analytical expressions for the mutual induction of two rectangular conductors with an arbitrary aspect ratio have been obtained. Results may be helpful in determining equilibrium configurations of domain structures in magnetic elements of spintronic devices, magnetic sensors and magnetic memory.

Ferroelastic phase transitions and domain structures in powders

2005 ◽  
Vol 220 (8) ◽  
Author(s):  
Hans Boysen
Keyword(s):  
Phase Transitions ◽  
Domain Walls ◽  
Approximate Model ◽  
Second Phase ◽  
High Symmetry ◽  
Line Profiles ◽  
Line Broadening ◽  
Rietveld Refinements ◽  
Domain Structures ◽  
Individual Line

AbstractPowder patterns of samples resulting from ferroelastic phase transitions generally show typical line profiles: asymmetry into the direction of the position of the corresponding hypothetical high symmetry reflection and strongly anisotropic line broadening. An approximate model is presented that describes the characteristic distribution of individual line widths based on the variation of lattice spacings within the domain walls. The variation with temperature is governed by the competition of decreasing spontaneous strain and increasing wall widths and/or wall densities. It is argued that conventional Rietveld refinements can easily lead to erroneous results and a simplified method is proposed to approximate the actual line profiles via the introduction of a second phase with anisotropic strain broadening to take into account the scattering fom the domain walls.

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