Non-Invasive Visualization of Ferroelectric Domain Structures on the Non-Polar y-Surface of KTiOPO4 via Raman Imaging

Potassium titanyl phosphate (KTP) is a nonlinear optical material with applications in high-power frequency conversion or quasi-phase matching in submicron period domain grids. A prerequisite for these applications is a precise control and understanding of the poling mechanisms to enable the fabrication of high-grade domain grids. In contrast to the widely used material lithium niobate, the domain growth in KTP is less studied, because many standard methods, such as selective etching or polarization microscopy, provides less insight or are not applicable on non-polar surfaces, respectively. In this work, we present results of confocal Raman-spectroscopy of the ferroelectric domain structure in KTP. This analytical method allows for the visualization of domain grids of the non-polar KTP y-face and therefore more insight into the domain-growth and -structure in KTP, which can be used for improved domain fabrication.

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TEM Observation on Ferroelectric Domain Structures of PbTiO3 Epitaxial Films

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.485.179 ◽

2011 ◽

Vol 485 ◽

pp. 179-182

Author(s):

Kenta Aoyagi ◽

Takanori Kiguchi ◽

Yoshitaka Ehara ◽

Hiroshi Funakubo ◽

Toyohiko J. Konno

Keyword(s):

Elastic Interaction ◽

Epitaxial Films ◽

Ferroelectric Domain ◽

Field Energy ◽

Domain Structures ◽

Domain Wall Energy ◽

Transmission Electron ◽

Ferroelectric Domain Structure ◽

Energy Domain ◽

Domain Length

The ferroelectric domain structure of PbTiO3(PTO) films was investigated by using transmission electron microscopy (TEM). In the film with PTO/SrTiO3(STO) structure, 180º domains are formed near the SrTiO3(STO) substrate and the domain length of 180º domains is 100 nm. However, 180º domains are not formed in the film with Pt/PTO/SrRuO3(SRO)/STO structure. These results show that 180º domains are formed in order to minimize depolarizing field energy, and that the domain length of 180º domains is determined by the competition among the depolarizing field energy, domain wall energy, Coulomb interaction and elastic interaction.

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Time dependence of domain structures in potassium sodium niobate-based piezoelectric ceramics

RSC Advances ◽

10.1039/d1ra03304b ◽

2021 ◽

Vol 11 (33) ◽

pp. 20057-20062

Author(s):

Jia Yang ◽

Zhipeng Gao ◽

Yi Liu ◽

Zhengwei Xiong ◽

Faqiang Zhang ◽

...

Keyword(s):

Domain Wall ◽

Time Dependence ◽

Domain Structure ◽

Piezoelectric Ceramics ◽

Ferroelectric Domain ◽

Sodium Niobate ◽

Potassium Sodium Niobate ◽

Potassium Sodium ◽

Domain Structures ◽

Ferroelectric Domain Structure

The ferroelectric domain structure of Li-doped (K,Na)NbO3 changed naturally as time passed, and most of the change occurred in the 180° domain wall, while the 60°/120° domains remained nearly unchanged.

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Ferroelectric Domain Structure of Pb(Zr.52Ti.48)03

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000933 ◽

1980 ◽

Vol 38 ◽

pp. 214-215

Author(s):

E.K. Goo ◽

R.K. Mishra

Keyword(s):

Phase Transformation ◽

Domain Structure ◽

Tetragonal Phase ◽

Ferroelectric Domain ◽

Cubic Phase ◽

Ion Milling ◽

Thin Foils ◽

Ferroelectric Domain Structure ◽

Ferroelectric Domains

Ferroelectric domains are twins that are formed when PZT undergoes a phase transformation from a non-ferroelectric cubic phase to a ferroelectric tetragonal phase upon cooling below ∼375°C.,1 The tetragonal phase is spontaneously polarized in the direction of c-axis, making each twin a ferroelectric domain. Thin foils of polycrystalline Pb (Zr.52Ti.48)03 were made by ion milling and observed in the Philips EM301 with a double tilt stage.

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Study on the "Phase Hopping" AC-AC Frequency Conversion Method with Approximately Continuous Frequencies

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096513999200611161226 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1217-1226

Author(s):

Zhengwang Xu ◽

Guozhuang Jiang ◽

Ke Kun ◽

Yuchun Yi

Keyword(s):

Output Voltage ◽

Frequency Conversion ◽

Frequency Control ◽

Actual Application ◽

Power Frequency ◽

Voltage Frequency ◽

The Law ◽

Large Cycle ◽

Selection Of ◽

Conversion Technology

Background: The output voltage frequency for the previously proposed "phase hopping" AC-AC frequency conversion technology is determined by the law that the number of output voltage cycles is reduced by one relative to the power frequency in a large cycle containing six jumps. According to the law, only a limited number of output frequencies, such as 37.5 Hz, 42.86 Hz and 45 Hz are found. Due to the large spacing between the output frequencies, the "phase hopping" frequency conversion technology is difficult to put into practical use. Methods: In this paper, the law of the output frequency control is generalized so that the number of output cycles in a large cycle is reduced by n relative to the power frequency. The analysis shows that the appropriate selection of large cycles, including the number of power frequency cycles and the value of n, can find more frequencies to be used. Reducing the interval between the output frequencies within 1Hz. Results: The analysis results were verified in simulation by MATLAB, and the harmonics and the feasibility of the actual application were analyzed. Conclusion: Finally, an experimental platform was built and an experimental analysis was carried out. The experimental results show that the theoretical and simulation analyses are correct.

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Advanced Micro-Actuator/Robot Fabrication Using Ultrafast Laser Direct Writing and Its Remote Control

Applied Sciences ◽

10.3390/app10238563 ◽

2020 ◽

Vol 10 (23) ◽

pp. 8563

Author(s):

Sangmo Koo

Keyword(s):

Three Dimensional ◽

Processing Technique ◽

Direct Writing ◽

Laser Direct Writing ◽

Precise Control ◽

Two Photon ◽

Non Invasive ◽

Acoustic Control ◽

Fs Laser ◽

Invasive Control

Two-photon polymerization (TPP) based on the femtosecond laser (fs laser) direct writing technique in the realization of high-resolution three-dimensional (3D) shapes is spotlighted as a unique and promising processing technique. It is also interesting that TPP can be applied to various applications in not only optics, chemistry, physics, biomedical engineering, and microfluidics but also micro-robotics systems. Effort has been made to design innovative microscale actuators, and research on how to remotely manipulate actuators is also constantly being conducted. Various manipulation methods have been devised including the magnetic, optical, and acoustic control of microscale actuators, demonstrating the great potential for non-contact and non-invasive control. However, research related to the precise control of microscale actuators is still in the early stages, and in-depth research is needed for the efficient control and diversification of a range of applications. In the future, the combination of the fs laser-based fabrication technique for the precise fabrication of microscale actuators/robots and their manipulation can be established as a next-generation processing method by presenting the possibility of applications to various areas.

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